
Class 
Book. 






f 



Copyright^ . 



COPYRIGHT DEPOSED 



Market Dairying 



BY 



JOHN MICHELS, B.S.A., M.S. (Wisconsin) 

Professor of Dairying and Animal Husbandry 

tn the State Agricultural College 

of North Carolina 

AUTHOR OF 

"CREAMERY BUTTER-MAKING" 

AND 

"DAIRY FARMING" 



ILLUSTRATED 



RALEIGH, NORTH CAROLINA 

Published by the Author 

i 9 o 9 

ALL RIGHTS RESERVED 



h 



y 



'[ 






COPYRIGHT, BY 

JOHN MICHELS 

1909 



LIBRARY of CONGRESS 
Two CoDies Received 

JUN lb lt*U» 

'class A m *"• 




PREFACE. 

Dairy instruction has hitherto been confined chiefly to 
the economical production of milk and the manufacture 
of butter and cheese. Yet those who have thoroughly 
studied the subject must admit that market dairying 
deserves fully as much attention as either the econom- 
ical production of milk or the manufacture of butter 
or cheese. 

The subject of market dairying presents two very im- 
portant aspects : One is to educate dairymen to produce 
better and more wholesome milk; the other is to instruct 
them in all the economies relating to their business so 
as to insure maximum financial returns. 

For a number of years the author has been brought 
face to face with the problems relating to market dairy- 
ing. He has been actively engaged in the production and 
marketing of sanitary milk and cream, and in the manu- 
facture and marketing of ice cream, cottage cheese, and 
skimmilk-buttermilk. The markets and dairy conditions 
of the country have been thoroughly investigated and 
new methods and plans have been developed, some of 
which have already been published in bulletin form or 
otherwise. 

The production of this volume is, therefore, largely the 
result of the knowledge and experience thus gained, and 
the realization of the urgent and increasing needs along 
this line of dairying. An attempt has been made to so 
arrange the material that it might answer the needs of 
both the classroom and the dairyman who cannot attend 
a dairy school. 

John Miches. 

April i, 1909. 



TABLE OF CONTENTS. 

Chapter. Page. 

I. Chemical and Physical Properties of Milk 7 

II. Bacteria in Milk 19 

III. Production of Sanitary Milk 23 

IV. Cooling and Aeration of Milk and Cream S3 

V. The Babcock Test 42 

VI. Creaming _ 52 

VII. Standardization of Milk and Cream 59 

VIII. Cold Storage 62 

IX. How to Secure a Good Market 69 

X. Retailing Milk and Cream 73 

XI. Shipping Milk and Cream 78 

XII. Washing and Sterilizing Milk Vessels 82 

XIII. Making and Marketing Cottage Cheese 90 

XIV. Making and Marketing Skimmilk-Buttermilk 98 

XV. Making and Marketing Ice Cream 101 

XVI. Relative Market Value of Milk and its Products.. 107 

XVII. Farm Buttermaking 1 1 1 

XVIII. The Dairy House 129 

XIX. Mechanical Refrigeration 136 

XX. Keeping Accounts 146 

XXI. Pasteurizing Milk and Cream 151 

XXII. Certified Milk 154 

XXIII. The Care of Milk in the Home 157 

XXIV. The Boiler and its [Management 159 

XXV. .Water and Ice Supply 170 

XXVI. Sewage Disposal from Dairy and Dwelling 176 

Appendix 182 

Index 189 



MARKET DAIRYING. 

CHAPTER I. 

CHEMICAL AND PHYSICAL PROPERTIES OF MILK. 



Milk, in a broad sense, may be defined as the normal 
secretion of the mammary glands of animals that suckle 
their young. It is the only food found in Nature con- 
taining all the elements necessary to sustain life. More- 
over it contains these elements in the proper propor- 
tions and in easily digestible and assimilable form. 




Microscopic appearance of milk showing relative size of fat globules and 
bacteria. — Russell's Dairy Bacteriology. 

Physical Properties. Milk is a whitish opaque fluid 
possessing a sweetish taste and a faint odor suggestive 
of cows' breath. It has an amphioteric reaction, that is, 

7 



8 MARKET DAIRYING 

it is both acid and alkaline. This double reaction is due 
largely to acid and alkaline salts and possibly to small 
quantities of organic acids. 

Milk has an average normal specific gravity of 1.032, 
with extremes rarely exceeding 1.029 and 1.033. After 
standing a few moments it loses its homogenous character. 
Evidence of this we have in the "rising of the cream." 
This is due to the fact that milk is not a perfect solution 
but an emulsion. All of the fat, the larger portion of the 
casein, and part of the ash are in suspension. 

In consistency milk is slightly more viscous than water, 
the viscosity increasing with the decrease in temperature. 
It is also exceedingly sensitive to odors, possessing great 
absorption properties. This teaches the necessity of plac- 
ing milk in clean pure surroundings. 

Chemical Composition. The composition of milk is 
very complex and variable, as will be seen from the fol- 
lowing figures: 

Average Composition of Normal Milk. A com- 
pilation of figures from various American Ex- 
periment Stations. 

Water 87. iff 

Lutter fat 3.9^ 

Casein 2.9$ 

Albumen 5:* 

Sugar 4.9^ 

Ash 7^ 

Fibrin Trace. 

Galactase Trace. 



100. 0$ 



The great variations in the composition of milk are 
shown by the figures from Koenig, given below : 



PROPERTIES OF MILK 9 

Maximum. Minimum. 

Water 90.69 80.32 

Fat 6.47 1.67 

Casein 4.23 1.79 

Albumen ,.. 1.44 .25 

Sugar 6.03 2. 11 

Ash 1. 21 .35 

These figures represent quite accurately the maximum 
and minimum composition of milk except that the maxi- 
mum for fat is too low. The author has known cows 
to yield milk testing 7.6% fat, and records show tests 
even higher than this. 

BUTTER FAT. 

This is the most valuable as well as the most variable 
constituent of milk. It constitutes about 83% of butter 
and is an indispensable constituent of the many kinds of 
whole milk cheese now found upon the market. It also 
measures the commercial value of milk and cream, and 
is used as an index of the value of milk for butter and 
cheese production. 

Physical Properties. Butter fat is suspended in milk 
in the form of extremely small globules numbering about 
100,000,000 per drop of milk. These globules vary con- 
siderably in size in any given sample, some being five 
times as large as others. The size of the globules is 
affected mostly by the period of lactation. As a rule the 
size decreases and the number increases with the advance 
of the period. In strippers' milk the globules are some- 
times so small as to render an efficient separation of the 
cream and the churning of same impossible. 

The size of the fat globules also varies with different 
breeds. In the Jersey breed the diameter of the globule 



10 MARKET DAIRYING 

is one eight-thousandth of an inch, in the Holstein one 
twelve-thousandth, while the average for all breeds is 
about one ten-thousandth. 

Night's milk usually has smaller globules than morn- 
ing's. The size of the globules also decreases with the 
age of the cow. 

The density or specific gravity of butter fat at ioo° F. 
is .91 and is quite constant. Its melting point varies 
between wide limits, the average being 92 F. 

Composition of Butter Fat. According to Richmond, 
butter fat has the following composition : 

Butyrin 3.85 ) 

Caproin 3 .60 I Soluble or volatile. 

Caprylin 55 \ 



Caprin 1.90 

Laurin 7. 40 

Myristin 20.20 

Palmitin 25.70 

Stearin 1.S0 

Olein, etc 35-00 



Insoluble or 
non-volatile. 



This shows butter fat to be composed of no less than 
nine distinct fats, which are formed by the union of 
glycerine with the corresponding fatty acids. Thus, buty- 
rin is a compound of glycerine and butyric acid ; palmitin, 
a compound of glycerine and palmitic acid, etc. The 
most important of these acids are palmitic, oleic, and 
butyric. 

Palmitic acid is insoluble, melts at 144 ° F., and forms 
(with stearic acid) the basis of hard fats. 

Oleic acid is insoluble, melts at 57 ° F., and forms the 
basis of soft fats. 



PROPERTIES OP MILK 11 

Butyric acid is soluble and is a liquid which solidifies 
at — 2° F. and melts again at 28 ° F. 

Insoluble Fats. A study of these fats is essential in 
elucidating the variability of the churning temperature 
of cream. As a rule this is largely determined by the 
relative amounts of hard and soft fats present in butter 
fat. Other conditions the same, the harder the fat the 
higher the churning temperature. Scarcely any two milks 
contain exactly the same relative amounts of hard and 
soft fats, and it is for this reason that the churning tem- 
perature is such a variable one. 

The relative amounts of hard and soft fats are influ- 
enced by: 

1. Breeds. 

2. Feeds. 

3. Period of lactation. 

4. Individuality of cows. 

The butter fat of Jerseys is harder than that of Hol- 
steins and, therefore, requires a relatively high churning 
temperature, the difference being about six degrees. 

Feeds have an important influence upon the character 
of the butter fat. Cotton seed meal and bran, for example, 
materially increase the percentage of hard fats. Gluten 
feeds and linseed meal, on the other hand, produce a soft 
butter fat. 

With the advance of the period of lactation the per- 
centage of hard fat increases. This chemical change, to- 
gether with the physical change which butter fat under- 
goes, makes churning difficult in the late period of lac- 
tation. 

The individuality of the cow also to a great extent 
influences the character of the butter fat. It is inherent 



12 MARKET DAIRYING 

in some cows to produce a soft butter fat, in others to 
produce a hard butter fat, even in cows of the same breed. 

Soluble Fats. The soluble or volatile fats, of which 
butyrin is the most important, give milk and sweet. cream 
butter their characteristic flavors. Butyrin is found only 
in butter fat and distinguishes this from all vegetable 
and other animal fats. 

The percentage of soluble fats decreases with the period 
of lactation, also with the feeding of dry feeds and those 
rich in protein. Succulent feeds and those rich in carbo- 
hydrates, according to experiments made in Holland and 
elsewhere, increase the percentage of soluble fats. This 
may partly account for the superiority of the flavor of 
June butter. 

It may be proper, also, to discuss under volatile or 
soluble fats those abnormal flavors that are imparted to 
milk, cream, and butter by weeds like garlic and wild 
onions, and by various feeds such as beet tops, rape, par- 
tially spoiled silage, etc. These flavors are undoubtedly 
due to abnormal volatile fats. 

Cows should never be fed strong flavored feeds shortly 
before milking. When this is done the odors are sure 
to be transmitted to the milk and the products therefrom. 
When, however, feeds of this kind are fed shortly after 
milking no bad effects will" be noticed at the next milking. 

Albumenoids. These are nitrogenous compounds 
which give milk its high dietetic value. Casein, albumen, 
globulin, and nuclein form the albumenoids of milk, the 
casein and albumen being by far the most important. 

Casein. This is a white colloidal substance, possessing 
neither taste nor smell. It is the most important tissue- 
forming constituent of milk and forms the basis of an 
almost, endless variety of cheese. 



PROPERTIES OF MILK 13 

The larger portion of the casein is suspended in milk 
in an extremely finely divided amorphus condition. It is 
intimately associated with the insoluble calcium phosphate 
of milk and possibly held in chemical combination with 
this. Its study presents many difficulties, which leaves its 
exact composition still undetermined. 

Casein is easily precipitated by means of rennet extract 
and dilute acids, but the resulting precipitates are not 
identically the same. It is not coagulated by heat. 

Albumen. In composition albumen very closely re- 
sembles casein, differing from this only in not containing 
sulphur. It is soluble and unaffected by rennet, which 
causes most of it to pass into the whey in the manufacture 
of cheese. It is coagulated at a temperature of 170 F. 
It is in their behavior toward heat and rennet that casein 
and albumen radically differ. 

Milk Sugar, This sugar, commonly called lactose, has 
the same chemical composition as cane sugar, differing 
from it chiefly in possessing only a faint sweetish taste. 
It readily changes into lactic acid when acted upon by 
the lactic acid bacteria. This causes the ordinary phenom- 
enon of milk souring. The maximum amount of acid in 
milk rarely exceeds .9%, the germs usually being checked 
or killed before this amount is formed. There is there- 
fore always a large portion of the sugar left in sour milk. 
All of the milk sugar is in solution. 

Ash. Most of the ash of milk exists in solution. It 
is composed of lime, magnesia, potash, soda, phosphoric 
acid, chlorine, and iron, the soluble lime being the most 
important constituent. It is upon this that the action of 
rennet extract is dependent. For when milk is heated 
to high temperatures the soluble lime is rendered insoluble 
and rennet will no longer curdle milk. It seems also that 



14 MARKET DAIRYING 

the viscosity of milk and cream is largely due to soluble 
lime salts. Cream heated to high temperatures loses its 
viscosity to such an extent that it can not be made to 
"whip." Treatment with soluble lime restores its orig- 
inal viscosity. The ash is the least variable constituent 
of milk. 

Colostrum Milk. This is the first milk drawn after 
parturition. It is characterized by its peculiar odor, yel- 
low color, broken down cells, and high content of albu- 
men which gives it its viscous, slimy appearance and 
causes it to coagulate on application of heat. 

According to Eugling the average composition of colos- 
trum milk is as follows : 

Water 71 .69^ 

Fat 337 

Casein 4.83 

Albumen 15.85 

Sugar 2.48 

Ash 1.78 

The secretion of colostrum milk is of very short dura- 
tion. Usually within four or five days after calving it 
assumes all the properties of normal milk. In .some cases, 
however, it does not become normal till the sixth or even 
the tenth day, depending largely upon the condition of 
the animal. 

A good criterion in the detection of colostrum milk is 
its peculiar color, odor, and slimy appearance. The dis- 
appearance of these characteristics determines its fitness 
for butter production. 

Milk Secretion. Just how all of the different con- 
stituents of milk are secreted is not yet definitely 
understood. But it is known that the secretion takes 



PROPERTIES OF MILK IS 

place in the udder of the cow, and principally during the 
process of milking. Further, the entire process of milk 
elaboration seems to be under the control of the nervous 
system of the cow. This accounts for the changes in flow 
and richness of milk whenever cows are subjected to 
abnormal treatment. It is well known that a change of 
milkers, the use of rough language, or the abuse of cows 
with dogs and milk stools, seriously affects the production 
of milk and butter fat. It is therefore of the greatest 
practical importance to milk producers to treat cows 
as gently as possible, especially during the process of 
milking. 

How Secreted. The source from which the milk con- 
stituents are elaborated is the blood. It must not be sup- 
posed, however, that all the different constituents already 
exist in the blood in the form in which we find them in 
milk, for the blood is practically free from fat, casein, 
and milk sugar. These substances must then be formed in 
the cells of the udder from material supplied them by the 
blood. Thus there are in the udder cells that have the 
power of secreting fat in a manner similar to that by 
which the gastric juice, is secreted in the stomach. Simi- 
larly, the formation of lactose is the result of the action 
of another set of cells whose function is to produce lac- 
tose. It is believed that the casein is formed from the 
albumen through the activity of certain other cells. The 
water, albumen, and soluble ash probably pass directly 
from the blood into the milk ducts by the process known 
as osmosis. 

Variations in the Qualit}' of Milk. Milk from dif- 
ferent sources may vary considerably in composition, 
particularly in the percentage of butter fat. Even the 



16 MARKET DAIRYING 

milk from the same cow may vary a great deal in compo- 
sition. The causes of these variations may be assigned 
to two sets of conditions : I. — Those natural to the cow. 
II.— Those of an artificial nature. 

I. QUALITY OF MILK AS AFFECTED BY NATURAL CONDI- 
TIONS. 

I. The composition of the milk of all cows undergoes 
a change with the advance of the period of lactation. 
During the first five months the composition remains prac- 
tically the same. After this, however, the milk becomes 
gradually richer until the cow "dries up." The following 
figures from Van Slyke illustrate this change: 

Month of Per cent of fat 

lactation. in milk. 



i 4 

2 : 4 

3 4 

4-. 4 

5 4 

6 4 

7 4 

8 4 

9 4 

io 5 



It will be noticed from these figures that the milk 
actually decreases somewhat in richness during the first 
three months of the period. But just before the cow dries 
up, it may test as high as 8%. 

2. The quality of milk also differs with different 
breeds. Yet breed differences are less marked than those 
of the individual cows of any particular breed. 

Some breeds produce rich milk, others relatively poor 



PROPERTIES OF MILK 



17 



milk. The following data obtained at the New Jersey 
Experiment Station illustrates these differences: 



Breed. 


Total 
Solids. 


Fat. 


Milk 
Sugar. 


Proteids. 


Ash. 


Ayshire 

Guernsey 

Hols-tein 

Tersev 


Per cent. 
12.70 
14.48 
12.12 
14.34 


Per cent. 
3.68 
5.02 
3.51 

4.78 


Per cent. 
4.84 
4.80 
4.69 

4.85 


Per cent. 
3.48 
3.92 
3.28 
3.96 


Per cent. 
.69 
.75 

.64 

.75 







3. Extremes in the composition of milk are usually 
to be ascribed to the individuality or "make up" of the 
cow. It is inherent in some cows to produce rich milk, 
in others to produce poor milk. In other words, Nature 
has made every cow to produce milk of a given richness, 
which can not be perceptibly changed except by careful 
selection and breeding for a number of generations. 



II. QUALITY OF MILK AS AFFECTED BY ARTIFICIAL CON- 
DITIONS. 

1. When cows are only partially milked they yield 
poorer milk than when milked clean. This is largely 
explained by the fact that the first drawn milk is always 
poorer in fat than that drawn last. Fore milk may test 
as low as .8%, while the strippings sometimes test as 
high as 14%. 

2. Fast milking increases both the quality and the 
quantity of the milk. It is for this reason that fast milkers 
are so much preferred to slow ones. 



18 MARKET DAIRYING 

3. The richness of milk is also influenced by the length 
of time that elapses between the milkings. In general, 
the shorter the time between the milkings the richer the 
milk. This, no doubt, in a large measure accounts for 
the differences we often find in the richness of morning's 
and night's milk. Sometimes the morning's milk is the 
richer, at other times the evening's, depending largely 
upon the time of day the cows are milked. Milk can not, 
however, be permanently enriched by milking three times 
instead of twice a day. 

4. Unusual excitement of any kind reduces the quality 
of milk. The person who abuses cows by dogs, milk 
stools, or boisterousness, pays dearly for it in a reduction 
ol both the quality and the quantity of milk produced. 

5. Starvation also seriously affects both the quality 
and the quantity of milk. It has been repeatedly shown, in 
this country and in Europe, that under-feeding to any 
great extent results in the production of milk poor in fat. 

6. Sudden changes of feed may slightly affect the 
richness of milk, but only temporarily. 

So long as cows are fed a full ration, it is not possible 
to change the richness of milk permanently, no matter 
what the character of feed composing the ration. 

7. Irregularities of feeding and milking, exposure to 
heat, cold, rain, and flies, tend to reduce both the quantity 
and the quality of milk produced. 



CHAPTER II. 

BACTERIA IN MILK. 

The term bacteria is applied to the smallest of living 
plants, which can be seen only under the highest powers 
of the miscroscope. Each bacterium is made up of a 
single cell. These plants are so small that it would 
require 30,000 of them laid side by side to measure an 
inch. Their presence is almost universal, being found 
in the air, water, and soil ; in cold, hot, and temperate 
climates ; and in living and dead as well as inorganic 
matter. 

Bacteria grow with marvelous rapidity. A single bac- 
terium is capable of reproducing itself a million times 
in twenty-four hours. They reproduce either by a simple 
division of the mother cell, thus producing two new cells, 
or by spore formation in which case the contents of the 
mother cell are formed into a round mass called a spore. 
These spores have the power of withstanding unfavorable 
conditions to a remarkable extent, some being able to 
endure a temperature of 21 2 F. for several hours. 

Most bacteria require for best growth a moist, warm, 
and nutritious medium such as is furnished by milk, in 
which an exceedingly varied and active life is possible. 

In nature and in many of the arts and industries, 
bacteria are of the greatest utility, if not indispensable. 
They play a most important part in the disintegration of 
vegetable and animal matter, resolving compounds into 
their elemental constituents in which form they can again 

19 



20 MARKET DAIRYING 

be built up and used as plant food. In the art of butter 
and cheese making bacteria are indispensable. The to- 
bacco, tanning, and a host of other industries cannot 
flourish without them. 

Lactic Acid Bacteria. In milk and cream intended 
for direct consumption, bacteria of any kind are enemies 
to dairymen. The class of bacteria that is feared more 
than any other, perhaps, is that which causes milk to 
sour. The organisms belonging to this class are known 
as lactic acid bacteria. They are non-spore bearing and 
grow best at a temperature of from 90 to 98 ° F. At 
40 F. their growth ceases; exposed to a temperature of 
140 for 15 minutes they are killed. 

The souring of milk and cream is due to the action 
of the lactic acid bacteria upon the milk sugar changing 
it into lactic acid. Acid is therefore always produced at 
the expense of milk sugar. But the sugar is never all 
converted into acid because the production of acid is 
limited. When the acidity reaches about .9% the lactic 
acid bacteria are either checked or killed and the pro- 
duction of acid ceases. Owing to the universal presence 
of these bacteria it is almost impossible to secure milk free 
from them. 

Under cleanly conditions the lactic acid type of bacteria 
always predominates in milk. When, however, milk is 
drawn under uncleanly conditions the lactic organisms 
may be outnumbered by other species of bacteria which 
give rise to the numerous taints often met with in milk. 

While the acid bacteria are objectionable in milk in- 
tended for direct consumption, in cream made into butter 
they are indispensable. The highly desirable aroma in 
butter is the result of the growth of these organisms in 
the process of cream ripening. There are a number of 



BACTERIA IN MILK 21 

different species of bacteria that have the power of pro- 
ducing lactic acid. Milk containing only lactic acid bac- 
teria is spoken of as a ''pure culture" or "starter." Such 
cultures are now a commercial product and should be 
used wherever fancy butter and cheese and sour milk 
products are desired. The method of using these pure 
cultures or starters is discussed in the chapter on cottage 
cheese making, page 90. 

Bacteria that Produce Taints and Bad Odors. 
While the lactic are the commonest bacteria of milk, 
there are always present many other types, some of which 
produce serious taints and bad odors. Bacteria of this 
kind are usually associated with filth, and dairies that be- 
come strongly infected with them show lack^of cleanliness 
in the care and handling of the milk. 

The commonest bad flavors produced by this class of 
bacteria may be designated as rancid, bitter, strong, gassy, 
oily, fishy, and putrefactive. In market milk these filth 
bacteria are objectionable not only because of the bad 
flavors they produce, but also because they are recognized 
as a common cause of infantile troubles, such as diarrhoea. 
The high mortality among bottle-fed babies has been 
shown to be largely due to drinking milk that has been 
produced under unsanitary conditions. 

Disease Producing Bacteria. Milk frequently be- 
comes infected with this class of bacteria through diseased 
cows, infected water, infected milk vessels, and diseased 
attendants. 

One of the commonest of the disease producing bacteria 
is the bacillus tuberculosis. This germ usually finds 
entrance into the milk in two ways : It may come from 
the cow directly through her milk, or it may gain access 
to the milk through the litter in the barn. No milk should 



22 MARKET DAIRYING 

be offered for sale except that produced from cows that 
have been shown to be free from tuberculosis by the 
tuberculin test. 

A common means of infecting milk is through the water 
used in the dairy. Many typhoid fever epidemics have 
been positively traced to milk infected with typhoid or- 
ganisms through the water supply. The purity of the 
water used in a dairy should be absolutely above sus- 
picion. 

Another means of spreading disease through milk is 
the milk bottle. Every dairyman will, at some time, have 
customers in whose families there is sickness, and bottles 
passing unsterilized from such homes to* healthy ones, 
are often the means of communicating the disease to the 
latter. Many instances of this kind are on record. The 
absolute necessity of sterilizing the milk bottles to pre- 
vent the spread of contagious diseases is too evident 
to require further discussion. 

Milkers and attendants who come in contact with per- 
sons suffering from contagious diseases, or who may 
themselves be afflicted with disease, should be rigidly 
excluded from the dairy. Over five hundred epidemics 
of various diseases, such as scarlet fever, diphtheria, 
typhoid fever, etc., have been directly traced to infected 
milk. 

With the large number of bacteria ordinarily found in 
milk and with the great variety of pathogenic organisms 
that are often disseminated by means of it, it behooves 
us to know under what conditions milk should be pro- 
duced and handled to reduce bacterial contamination to 
a minimum. These conditions will be discussed in the 
following chapter. 



CHAPTER III. 

SANITARY MILK PRODUCTION. 

Sanitary Milk Defined. Sanitary milk is milk from 
healthy cows, produced and handled under conditions in 
which contamination from filth, bad odors, and bacteria, 
is reduced to a minimum. 

Importance of Sanitary Milk. The production of 
clean milk is one of the most important subjects that con- 
fronts the American dairyman at the present time. Fur- 
ther improvement in the quality of butter and cheese must 
largely be sought in the use of cleaner milk. With the 
better appreciation by the public of the great nutritive 
value of milk, there opens an unlimited market for it for 
consumption in the raw form. Already we find that milk 
produced under the best sanitary conditions sells for prac- 
tically double that obtained under ordinary, more or less, 
slip-shod conditions. So great is the clamor for cleaner 
milk that any extra efforts expended in producing it are 
certain to be richly compensated. 

The Necessary Conditions for the production of sani- 
tary milk are as follows: (i) Healthy cows; (2) sani- 
tary barn; (3) clean barn yard; (4) clean cows; (5) 
clean milkers; (6) clean milk vessels; (7) clean, whole- 
some feed; (8) pure water; (9) clean strainers; (10) 
dust-free stable air; (11) clean bedding; (12) milking 
with dry hands; (13) thorough cooling of milk after 
milking; (14) sanitary milk room. 

Healthy Cows. The health of the cow is of prime im- 
portance in the production of sanitary milk. All milk 

23 



24 MARKET DAIRYING 

from cows affected with contagious diseases should be 
rigidly excluded from the dairy. Aside from the general 
unfitness of such milk there is danger of the disease pro- 
ducing organisms getting into the milk. It has been 
found, for example, that cows whose udders are affected 
with tuberculosis, yield milk containing these organisms. 
The prevalence of this disease among cows at present 
makes it imperative to determine definitely whether or 
not cows are affected with the disease, by the application 
of the tuberculin test. 

Any feverish condition of the cow tends to impart a 
feverish odor to the milk, which should therefore not be 
used. Especially important is it that milk from diseased 
udders, no matter what the character of the disease, be 
discarded. 

Sanitary Barn. Light, ventilation, and ease of clean- 
ing are essential to a sanitary dairy barn. The disinfect- 
ant action of an abundance of sunlight, secured by pro- 
viding a large number of windows, is of the highest im- 
portance. 

Of equal importance is a clean, pure atmosphere, secur- 
ed by a continuous ventilating system. The fact that 
odors of any description are absorbed by milk with great 
avidity, sufficiently emphasises the great need of pure air. 

To permit of easy cleaning, the barn floors and gutters 
should be built of concrete. They should be scrubbed 
daily, and care should be taken to keep the walls and 
ceiling free from dust and cobwebs. The feed boxes must 
also be cleaned after each feed. 

The stalls should be of the simplest construction, to 
afford as little chance for lodgement of dust as possible. 
Furthermore, they should so fit the cows as to cause the 
latter to stand with their hind feet on the edge of the gut- 



SANITARY MILK PRODUCTION 25 

ter, a matter of the highest importance in keeping cows 
clean. 

The walls and ceiling should be as smooth as possible. 
Moreover, they should be frequently disinfected by means 
of a coat of whitewash. The latter gives the barn a 
striking sanitary appearance. 

Clean Barn Yard. A clean, well drained barn yard is 
an essential factor in the production of sanitary milk. 
Where cows are obliged to wade in mire and filth, it is 
easy to foretell what the quality of the milk will be. To 
secure a good barn yard it must be covered with gravel 
or cinders, and should slope away from the barn. If the 
manure is not taken directly from the stable to the fields, 
it should be placed where the cows cannot have access 
to it. 

Clean Cows. Where the barn and barn-yard are sani- 
tary, cows may be expected to be reasonably clean. Yet 
cows that are apparently clean, may still be the means of 
infecting milk to no small degree. When we consider 
that every dust particle and every hair that drops into 
the milk may add hundreds, thousands, or even millions 
of bacteria to it, we realize the importance of taking every 
precaution to guard against contamination from this 
source. 

To keep cows as free as possible from loose hair and 
dust particles they should be carded and brushed regu- 
larly once a day. This should be done after milking to 
avoid dust. Five to ten minutes before the cow is milked 
her udder and flanks should be gently washed with clean, 
tepid water, by using a clean sponge or cloth. This will 
allow sufficient time for any adhering drops of water to 
drip off, at the same time it will keep the udder and flanks 
sufficiently moist to prevent dislodgment of dust particles 



26 MARKET DAIRYING 

and hairs at milking time. This practically means that 
the milker must always have one or two cows washed 
ahead. He should be careful to wash his hands in clean 
water after each washing. 

Under ordinary conditions the cow is the greatest 
source of milk contamination. The rubbing of the milker 
against her and the shaking of the udder will dislodge 
numerous dust particles and hairs unless the foregoing 
instructions are rigidly followed. 

Attention should also be given to the cow's switch, 
which should be kept scrupulously clean. The usual 
switching during milking is no small matter in the con- 
tamination of milk when the switch is not clean. 

Clean Milkers. Clothes which have been worn in the 
fields are not suitable for milking purposes. Every milker 
should be provided with a clean, white milking suit, con- 
sisting of cap, jacket and trousers. Such clothes can be 
bought ready made for one dollar ; and, if frequently 
laundered, will materially aid in securing clean milk. 




Fig. 1. Unflushed seain. Fig. 2. Flushed seam. 

Milkers should also wash and dry their hands before 
milking, and, above all, should keep them dry during 
milking. 

Clean Vessels. All utensils used in the handling of 



SANITARY MILK PRODUCTION 27 

milk should be made of good tin, with as few seams as 
possible. Wherever seams occur, they should be flushed 
with solder. Unflushed seams are difficult to clean, and, 
as a rule, afford good breeding places for bacteria. Fig. 
i illustrates the character of the unflushed seam; Fig. 2 
shows a flushed seam, which fully illustrates its value. 

Fig. 3 illustrates a modern sanitary milk pail. The 
value of a partially closed pail is evident from the re- 
duced opening, which serves to keep out many of the 
micro-organisms that otherwise drop into the pail during 




Fig. 3. Sanitary Milk Tail. 

milking. While such a pail is somewhat more difficult 
to clean than the ordinary open pail, it is believed that 
the reduced contamination during milking far outweighs 
this disadvantage. 

All utensils used in the handling of milk should be as 
nearly sterile as possible. A very desirable method of 
cleaning them is as follows : 

First, rinse with warm or cold water. Second, scrub 



28 MARKET DAIRYING 

with moderately hot water containing some sal soda. 
The washing should be done with brushes rather than 
cloth because the bristles enter into any crevices present 
which the cloth cannot possibly reach. Furthermore, it 
is very difficult to keep the cloth clean. Third, scald 
thoroughly with steam or hot water, after rinsing out the 
water in which the sal soda was used. After scalding, 
the utensils should be inverted on the shelves without 
wiping and allowed to remain in this place until ready 
to use. This will leave the vessels in a practically sterile 
condition. Fourth, if it is possible to turn the inside of 
the vessels to the sun, in a place where there is no dust, 
then it is desirable to expose the utensils during the day 
to the strong germicidal action of the direct sun's rays. 

Clean, Wholesome Feed. Highly fermented and 
aromated feeds, like sour brewers grains and leeks should 
be rigidly withheld from dairy cows when anything like 
good flavored milk is sought. So readily does milk 
absorb the odors of feeds through the system of the ani- 
mal, that even good corn silage, when fed just previous 
to milking, will leave its odor in the milk. When fed 
after milking, however, no objection whatever can be 
raised against corn silage because not a trace of its odors 
is then found in the milk. Aromatic feeds of any kind 
should always be fed after milking. 

Pure Water. Since feeds are known to transmit their 
odors to the milk through the cow, it is reasonable to ex- 
pect water to do the same. Cows should, therefore, never 
be permitted to drink anything but pure, clean-flavored 
water. The need of pure water is further evident from 
the fact that it enters so largely into the composition of 
milk. 



SANITARY MILK PRODUCTION 29 

The water of ponds and stagnant streams is especially 
dangerous. Not only is such water injurious to the health 
of cows, but in wading into it, they become contaminated 
with numerous undesirable bacteria, some of which may 
later find their way into the milk. 

Strainers and Straining. Milk should be drawn so 
clean as to make it almost unnecessary to strain it. This 
operation is frequently done under the delusion that so 
long as it removes all visible dirt the milk has been 
entirely purified. The real harm, however, that comes 
from hairs and dust particles dropping into the milk is 
not so much in the hairs and dust particles themselves 
as in the millions of bacteria which they carry with them. 
These bacteria are so small that no method of straining 
will remove them. Straining can not even remove all 
of the dirt, because some of it will go in solution. 

A good strainer consists of two thicknesses of cheese 
cloth with a layer of absorbent cotton between. The 
strainer is to be placed on the can or vat into which the 
milk is to be strained and not on the milk pail. While 
a strainer like the above placed upon the milk pail, reduces 
the bacterial content slightly in the hands of careful milk- 
ers, it is believed that the slight advantage gained would 
be more than off-set by greater carelessness in milking; 
especially might this be true with ignorant milkers who 
are apt to think that the strainer will make up for any 
carelessness on their part. A cheese cloth strainer on 
the milk pail is worse than useless with any kind of 
milker. 

New sterilized cotton must be used at each milking 
and the cloths must be thoroughly washed and sterilized. 
Like the cotton, it is best to use the cloth but once. 

Dust=Free Air. Great precaution should be taken not 



30 MARKET DAIRYING 

to create any dust in the stable about milking time, for 
this is certain to find its way into the milk. Cows should, 
therefore, never be bedded or receive any dusty feed just 
before or during milking. 

Dry roughage, such as hay and corn fodder, always 
contains a considerable amount of dust, and when fed 
before or during milking may so charge the air with dust 
as to make clean milk an impossibility. 

Moistening the floor and walls with clean water pre- 
vious to milking materially minimizes the danger of get- 
ting dust into the milk. A mistake not infrequently made 
even in the better class of dairies is to card and brush the 
cows just before milking. While this results in cleaner 
cows, the advantage thus gained is far more than off- 
set by the dirtier air, which, as will be shown later, 
materially increases the germ content of the milk. The 
carding and brushing should be done at least thirty min- 
utes before the milking commences. 

Clean Bedding. Clean shavings and clean cut straw 
should preferably be used for bedding. Cows stepping 
and lying on dirty bedding will soil themselves and create 
a dusty barn air. 

Milking With Dry Hands. A prolific source of 
milk contamination is the milking with wet hands. Where 
the milker wets his hands with milk, some of it is bound 
to drip into the pail, carrying with" it thousands or mil- 
lions of bacteria, depending upon the degree of cleanliness 
of the milker's hands and the cow's udder. There is no 
excuse for the filthy practice of wet milking-, since it 
is just as easy to milk with dry hands. 

Fore=Milk. Where the purest milk is sought, it is de- 
sirable to reject the first stream or two from each teat, 
as this contains many thousands of bacteria. The reason 



SANITARY MILK PRODUCTION 31 

for this rich development of germs is found in the favor- 
able conditions provided by the milk in the milk-ducts of 
the teats, to which the bacteria find ready access. 

Flies. Flies not only constitute a prolific but also a 
dangerous source of milk contamination. These pests 
visit places of the worst description and their presence 
in a dairy suggests a disregard for cleanliness. Of 414 
flies examined by the 'Bacteriologist of the Connecticut 
Station, the average number of bacteria carried per fly 
was one and a quarter millions. Flies should be rigidly 
excluded from all places where they are apt to come in 
contact with the milk. 

Experimental Data. To show to what extent the 
bacterial content of milk may be reduced by adopting 
the precautions suggested in the foregoing pages, a few 
experimental data are herewith presented. 

In Bulletin No. 42 of the Storrs (Conn.) Experiment 
Station, Stocking reports the following : 

1. When the cows were milked before feeding the 
number of bacteria per c. c. was 1,233; when milked im- 
mediately after feeding, the number of bacteria was 3,656, 
or three times as many. 

2. When the udder and flanks of the cows were wiped 
with a damp cloth, the number of bacteria per c. c. was 
716; when not wiped the number was 7,058, or ten times 
as great. 

3. When the cows were not brushed just before milk- 
ing the number of bacteria per c. c. was 1,207; when 
brushed just before milking, the number was 2,286, or 
nearly twice as great. 

4. When students who had studied the production of 
clean milk did the milking, the number of bacteria per 
c. c. was 914; when the milking was done by regular 



32 



MARKET DAIRYING 



unskilled milkers the number of bacteria was 2,846, or 
three times as great. 

Wiping or washing udders before milking not only 
very materially reduces the bacterial content of the milk, 
but also lessens the amount of dirt to a very great extent. 
Frazer has shown that "the average weight of dirt which 
falls from muddy udders during milking is ninety times 
as great as that which falls from the same udder after 
washing, and when the udder is slightly soiled it is 
eighteen times as great." 




Clean Milking. (From Da. Div., U. S. Dept. of A.) 



CHAPTER IV. 

COOLING AND AERATION OF MILK AND CREAM. 

Importance of Low Temperature. Milk always con- 
tains bacteria no matter how cleanly the conditions under 
which it is drawn. At ordinary temperatures these bac- 
teria increase with marvelous rapidity ; at low tempera- 
tures their growth practically ceases. The effect of tem- 
perature on bacterial development is graphically shown 
in Fig. 4. 




Fig. 4. — Relation of temperature to bacterial growth. 

a represents a single bacterium; b, its progeny in twenty-four hours in 
milk kept at 50° F.; c, its progeny in twenty-four hours in milk kept at 70° F. 
(Bui. 26, Storrs, Conn.) 

At a temperature of 50 F. the bacteria multiplied five 
times ; at 70 ° F. they multiplied seven hundred and fifty 
times. 

Roughly speaking, at 98 F. bacteria multiply one hun- 

3 33 



34 MARKET DAIRYING 

dred times faster than at 70 ° F. At $2° F. bacterial de- 
velopment practically ceases. 

Milk or cream may be kept sweet a long time at 40 
to 45 F. because the lactic acid bacteria practically stop 
growing at these temperatures. But there are other 
classes of bacteria that can grow at these temperatures, 
as evidenced by the production of undesirable flavors. 
Such flavors usually become noticeable after thirty-six 
hours. Where milk and cream are to be kept in the best 
possible condition, it is necessary to reduce the tempera- 
ture to within a few degrees of freezing. 

Lack of thorough cooling necessitates two deliveries of 
milk per day, and, what is still worse, requires many 
dairymen to milk their cows shortly after midnight and 
shortly after midday, a drudgery which casts a damper 
upon the whole milk business. Lack of cooling also means 
financial loss through souring of milk and leads to many 
dissatisfied customers. 

Prompt Cooling. Milk should be cooled as quickly 
as possible after it is drawn. Indeed, the milk should be 
taken directly from the cow to the cooling room and 
promptly cooled. To do this conveniently it is necessary 
to have the cooling room located as near the barn as is 
consistent with freedom from barn odors. 

Too often the milk is allowed to remain in the barn 
until all the cows have been milked, and this may require 
from two to three hours, depending upon the number 
of cows milked by each milker. A few hours delay in 
cooling reduces the keeping quality of milk to a far greater 
extent than is commonly supposed. 

Importance of Aeration. Milk not only con- 

tains bacteria immediately after it is drawn, but it 
also contains gases, chief among which, perhaps, is car- 



COOLING AND AERATION 35 

bonic acid gas. These gases should be removed as quickly 
as . possible after milking by exposing the milk in thin 
sheets to the atmosphere. Fortunately the construction 
of modern coolers is such as to make it possible to do 
the cooling and aerating in one operation. 

Formerly it was customary for dairymen to aerate 
their milk before cooling. Such practice is known to give 
somewhat better aeration than is possible where the cool- 
ing and aerating are performed in the same operation ; 
yet the difference is so slight that consumers cannot detect 
it. The practice of aerating: first and cooling afterward 
is therefore being abandoned. 

Coolers. All modern coolers permit cooling with ice 
water. Without this a sufficiently low temperature can- 
not be obtained to stop practically all bacterial growth. 
To meet the requirements of dairies of different sizes, sev- 
eral styles of coolers are herewith described and illus- 
trated. 

Corrugated Cooler. This style of cooler is shown in 
Fig. 5, which also shows a desirable method of fastening 
it. It is especially adapted to dairies having from fifteen 
to thirty cows. The cooler consists of two parts : An 
upper section which is used to cool milk and cream with 
uniced water, and a lower section through which ice water 
is circulated. 

A storage tank for well water may be placed above 
the ceiling. From this the water is admitted to the upper 
section through the valve which is used to regulate 
the flow. As shown by the arrows the water enters the 
section at the bottom and discharges at the top. The 
waste water may be conducted to the feed water tank of 
the boiler, to a watering trough, or other places where 
it may be useful. 



36 



MARKET DAIRYING 



UAJ 



:3r 



Milk Reservoir 



.Floor , 



"^Ceu-ino 



FQ-- 



WeilWater 

CoOLEDbECT\ON 



-v 



IceVJaxeh 



Fig. 5.— Showing Corrugated Cooler and Method of Support. 

By means of the pump at the left, the ice water is 
forced back into the small tank at the right, which con- 
tains finely crushed ice. 



COOLING AND AERATION 



37 



As might be expected, by forcing the ice water from 
the cooler back into the ice water storage, a considerable 
saving is effected, not only of ice and water, but of time 
as well. Proof of these advantages is brought out by the 
results recorded in the following table, which shows the 
work of the cooler with and without the ice water pump. 
When no pump was used, ordinary well water was 
sprayed over finely crushed ice in the can shown at the 
right, and the discharge was allowed to run into the 
drain. 



Table Showing Work of Cooler With and Without the 

Pump. 



Number of Experiment. 


Amount 
Ice Used- 
Pounds. 


Time in 
Cooling — 
Minutes. 


Tempera- 
ture of 
Milk Be- 
fore Cool- 
ing—De- 
grees F. 


Tempera- 
ture of 
Well Wa- 
ter—De- 
grees F. 


( With pump 

No. 1 -j 

( Without pump 


37 

89 


45 
92 


85 
88 


73 
73 


( With pump. 

No. 3 ] 

( Without pump 


35 

94 


40 

82 


85 
84 


66 
66 


(With pump 

No. 3 ] 

( Without pump 


32 

85 


35 
93 


82 
85 


64 
64 


( With pump 

No. 4 ] 

( Without pump 


38 
95 


45 
85 


88 
85 


72 
72 


1 With pump 

No. 5 < 

( Without pump 


34 

83 


43 

88 


85 
88 


70 
70 


i With pump 

Average-; 

( Without pump 


35 

89 


41 

88 


85 
86 


69 



38 



MARKET DAIRYING 



All the milk was cooled to 45 ° F., and the amount of 
milk cooled in each experiment was forty-four gallons, 
one-half of which was cooled with a pump and the other 
half without. 

The above figures show that less than half the amount 
of ice and less than half as much time were required 
in cooling with the pump than when no pump was used. 

Where no ice is intended to be used, coolers may be 
purchased without the ice water section. 



SPRING WATER 
DISCHARGE 




SPRING WATER 
SUPPLY 



ICE WATER 
RETURN 



ICE WATER 
$ SUPPLY 



Fig. 6.— Tubular Cooler. 



The cooler is fastened by means of two-inch gal- 
vanized iron gas pipes, the lower ends of which are em- 
bedded in the concrete floor while the upper ends are at- 



COOLING AND AERATION 



39 



tached to the ceiling (Fig. 5). The milk reservoir -is also 
supported by galvanized iron gas pipes, in the manner 
shown in the illustration. 

The water pump should be fastened to the concrete 
floor in a manner similar to that in which the cream 
separator is fastened (see page 57). 

Tubular Cooler. Fig. 6 illustrates this type of cooler, 
which is recommended for dairymen having thirty or 
more cows. This cooler is very substantial, and, as a 
rule, has greater width in proportion to length than the 
corrugated style, which leaves the top of the cooler a 
more convenient distance from the floor. It may be 
fastened and operated in the same manner as the corru- 
gated cooler shown in Fig. 5. 

Cone=Shaped Cooler. 
For dairies having fewer 
than fifteen cows a cheap 
cooler like that shown in 
Fig. 7 may be used to 
advantage. The water 
enters the bottom of the 
cooler and discharges at 
the top, while the milk 
flows in a thin sheet over 
the outside. Ice may be 
placed inside the cooler, 
if desired. The can at 
the top is the milk re- 
ceiver, which has small 
openings at the bottom near the outside, through which 
the milk discharges in fine streams, directly upon the 
cOne below. 

Cooling With Brine. This is the cleanest, most con- 




Fig. 7.— Cone Shaped Cooler. 



40 MARKET DAIRYING 

venient and efficient, and, in many cases, the cheapest 
method of cooling milk and cream. The brine may be 
reduced to any temperature desired with a mechanical 
refrigerating machine. It is forced through the cooler 
with a pump, in the same manner as ordinary ice water. 
With the latter it is difficult to cool milk and cream below 
40 F., while with the brine the temperature is easily re- 
duced to 34 F., at which milk and cream remain prac- 
tically without change. Such a low temperature is espe- 
cially desirable in shipping milk and cream. When cream 
leaves the dairy at a temperature near freezing, it may 
be shipped in an ordinary can wrapped with a felt jacket 
a distance of 500 miles or more in warm weather without 
undergoing a noticeable change in either flavor or acidity. 

Precautions. in Cooling. While cooling milk or 
cream, the room should be kept damp, especially the 
floor. This will keep down any dust that may be in the 
room and thus keep it from getting into the milk. 
Draughts should be avoided during cooling for the same 
reason. In this connection it is well to remember that 
the real harm is not so much in the dust particles them- 
selves as in the many bacteria which usually adhere to 
them. 

Where coolers are left exposed to the air of the room 
after they have been cleaned and sterilized, they should 
be rinsed of! with boiling water just before using. 

It is important also to use a reliable thermometer. 
Ordinary cheap thermometers often read two to six de- 
grees too high or too low. A standard thermometer 
should be on hand, by which the cheaper ones may be 
standardized. 

Never Use Ice in Milk or Cream. Adding ice di- 
rectly to milk and cream is a pernicious, though not un- 



COOLING AND AERATION 41 

common, practice. The best of natural ice contains dirt 
and bacteria. Even ice made by mechanical means from 
distilled water often contains considerable quantities of 
impurities. Ice also is an adulterant just as much as 
water. In case of cream cooled with ice the body is un- 
satisfactory, even if the cream contains the required 
amount of fat. 



CHAPTER V. 



the: babcock test. 



This is a cheap and simple device for determining the 
percentage of fat in milk, cream, skim-milk, buttermilk, 
whey, and cheese. It was invented in 1890 by Dr. S. M. 
Babcock, of the Wisconsin Agricultural Experiment Sta- 
tion, and ranks among the leading agricultural inventions 
of modern times. The chief uses of the Babcock test may 
be mentioned as follows : 

1. It has made possible the payment for milk accord- 
ing to its quality. 

2. It has enabled butter and cheese makers to detect 
undue losses in the process of manufacture. 

3. It has made possible the grading up of dairy herds 
by locating the poor cows. 

4. It has, in a large measure, done away with the prac- 
tice of watering and skimming milk. 

Principle of the Babcock Test. The separation of 
the butter fat from milk with the Babcock test is made 
possible : 

1. By the difference between the specific gravity of 
butter fat and milk serum. 

2. By the centrifugal force generated in the tester. 

3. By burning the solids not fat with a strong acid. 
Sample for a Test. Whatever the sample to be tested, 

always eighteen grams are used for a test. In testing 
cream and cheese, the sample is weighed. For testing 
milk, skim-milk, buttermilk, and whey, weighing requires 

42 



THE BABCOCK TEST 43 

too much time. Indeed, with these substances weighing 
is not necessary as sufficiently accurate samples are ob- 



Fig. 8 -Two styles of Babcock testers. 

tained by measuring which is the method universally em- 
ployed. In making a Babcock test it is of the greatest 
importance to secure a uniform sample of the substance 
to be testedc 



44 MARKET DAIRYING 

Apparatus. This consists .essentially of the following 
parts : A, Babcock tester ; B, milk bottle ; C, cream bottle ; 
D, skim-milk bottle ; E, pipette or milk measure ; F, acid 
measures ; G, cream scales ; H, mixing cans ; I, dividers. 

A. Babcock Tester. x This machine, shown in Fig. 8, 
consists of a revolving wheel placed in a horizontal posi- 
tion and provided with swinging pockets for the bottles. 
This wheel is rotated by means of a worm wheel (lower 
machine) at the top of the tester. When the tester stops 
the pockets hang down allowing the bottles to stand up. 
As the wheel begins rotating the pockets move out causing 
the bottles to assume a horizontal position. The wheel is 
enclosed in a cast iron frame provided with a cover. 

B. Milk Bottle. This has a neck graduated to ten 
large divisions, each of which reads one per cent. Each 
large division is subdivided into five smaller ones, 
making each subdivision read .2%. The contents of the 
neck from the zero mark to the io% mark is equivalent to 
two cubic centimeters. Since the Babcock test does not 
give the percentage of fat by volume but by weight, the 
io% scale on the neck of the bottle will, therefore, hold 
i.8 grams of fat. In other words, if the scale were filled 
with water it would hold two grams ; but fat being only 
.9 as heavy, 2 cubic centimeters of it would weigh nine- 
tenths of two grams or 1.8 grams. This is exactly io% 
of 1 8 grams, the weight of the sample used for testing. 
A milk bottle is shown in Fig. 9. 

C. Cream Bottles. These are graduated from 30% to 
55%. A 30% bottle is shown in Fig. 10. Since cream 
usually tests more than 30%, the sample must be divided 
wher. the 30% bottles are used. 



THE BABCOCK TEST 



45 



Fig. 10.— Cream 
bottle. 



WR8 



>+474\ 



Fig. 11.— Skim-milk 
bottle. 



D. Skim=milk Bottle. This bottle, shown in Fig. 1 1 , 
is provided with a double neck, a large one to admit the 
milk, and a smaller graduated neck for fat reading. The 
entire scale reads one-half per cent. Being divided into 
ten subdivisions each subdivision reads .05%. The same 
bottle is also used for testing buttermilk. 



46 



MARKET DAIRYING 




Fig. 14.— 
Acid meas- 
ure. 



E. Pipette. This holds 17.6 c.c, as shown 
in Fig. 12. Since about .1 c.c. of milk will 
adhere to the inside of the pipette it is ex- 
pected to deliver only 17.5 c.c, which is equiva- 
lent to 18 grams of normal milk. 

F. Acid Measures. In making a Babcock 
test equal quantities, by volume, of acid and 
milk are used. The acid measure, shown in 

Fig. 13, holds 17.5 c.c. of acid, the amount needed for one 
test. The one shown in Fig. 14 is divided into six divisions, 
each of which holds 17.5 ex. or one charge of acid. Where 



THE BABCOCK TEST 



47 



many tests are made a graduate of this kind saves time 

in filling, but should be made to hold twenty-five charges. 

H. A cream scales commonly used is illustrated in 

Fig- 15- 

Acid. The acid used in the test is commercial sul- 




Fig. 15.— Cream scales. 

phuric acid having a specific gravity of 1.82 
to 1.83. When the specific gravity of the 
acid falls below 1.82 the milk solids are not 
properly burned and particles of curd may 
appear in the fat. On the other hand, an 
acid with a specific gravity above 1.83 has 
a tendency to blacken or char the fat. 

The sulphuric acid, besides burning the 
solids not fat, facilitates the separation of 
the fat by raising the specific gravity of the 
medium in which it floats. 

Sulphuric acid must be kept in glass bot- 
tles provided with glass stoppers. Exposure 
to the air materially weakens it. 

Making a Babcock Test. The different 
indicated as follows : 

1. Thoroughly mix the sample. 

2. Immediately after mixing insert the pipette into 
the milk and suck until the milk has gone above the mark 
on the pipette, then quickly place the fore finger over the 




Fig. 16. -Show- 
ing manner of 
emptying pi- 
pette. 

steps are 



48 



MARKET DAIRYING 



top and allow the milk to run down to the mark by slowly 
relieving the pressure of the ringer. 

3. Empty the milk into the bottle in the manner shown 
in Fig. 16. 

4. Add the acid in the same manner in which the milk 
was emptied into the bottle. 

5. Mix the acid with the milk by giving the bottle a 
slow rotary motion. 

6. Allow mixture to stand a few minutes. 

7. Shake or mix again and then place the bottle in 
the tester. 

8. Run tester four minutes at the 
proper speed. 

9. Add moderately hot water until 
contents come to the neck of the " 
bottle. 

10. Whirl one minute. 

11. Add moderately hot water un- 
til contents of the bottle reach about 
the 8% mark. 

12. Whirl one minute. 

13. Read test. 



How to Read Milk Test. At the 

top of the fat column is usually quite a 
pronounced meniscus as shown in Fig. 
17. A less pronounced one is found 
at the bottom of the column. The fat 
should be read from the extremes of 
the fat column, 1 to 3, not from 2 to 4, 
when its temperature is about 140 F. 
Too high a temperature gives too high 



8 



Fig. 17.— Fat column 
showing meniscuses. 



THE BABCOCK TEST 49 

a reading, because of the expanded condition of the fat, 
while too low a temperature gives an uncertain reading. 
Precautions in Making a Test. I. Be sure you have 
a fair sample. 

2. The temperature of the milk should be about 60 
or 70 degrees. 

3. Always mix twice after acid has been added. 

4. Be sure your tester runs at the right speed. 

5. Use nothing but clean, soft water in filling the 
bottles. 

6. Be sure the tester does not jar. 

7. 'Be sure the acid is of the right strength. 

8. Mix as soon as acid is added to milk. 

9. Do not allow the bottles to become cold before 
reading the test. 

10. Read the test twice to insure a correct reading. 
The water added to the test bottles after they have been 

whirled should be clean and pure. Water containing 
much lime seriously affects the test. Such water may 
be used, however, when first treated with a few drops of 
sulphuric acid. 

As stated before, skim-milk, buttermilk, and cream are 
tested in the same way as milk, with the exception that 
the cream sample is weighed, not measured. (See p. 51.) 

Testing Cream. Accurate tests of cream cannot be 
secured by measuring the sample into the bottle as is 
done in the case of milk. The reason for this is that 
the weight of cream varies with its richness. The richer 
the cream the less it weighs per unit volume. This is illus- 
trated in the following table by Farrington and Woll : 



50 MARKET DAIRYING 

Weight of fresh separator cream delivered by a 17.6 c. c. 

pipette. 



Per cent, of fat 


Specific gravity 


Weight of cream 


in cream. 


(weighed). 


in grams. 


10 


1.023 


17.9 


15 


I.0I2 


177 


20 


1.008 


17-3 


25 


1.002 


17.2 


30 


.996 


17.0 


35 


.980 


16.4 


40 


.966 


16.3 


45 


•950 


16.2 


50 


•947 


15-8 



With cream testing below 30% the full 18 grams may 
be added to one bottle and tested in the usual way. Where 
the cream tests above 30% better results are obtained by 
using only half the full sample of cream (9 grams) 
and adding to this 9 grams of water. To this mixture 
the full amount of acid is added. Obviously in this case 
the test must be multiplied by 2 to get the correct reading. 

General Pointers. Black fat is caused by 

1. Too strong acid. 

2. Too much acid. 

3. Too high a temperature of the acid or the milk. 

4. Not mixing soon enough. 

5. Dropping the acid through the milk. 

Foam on top of fat is caused by hard water, and can 
be prevented by adding a few drops of sulphuric acid to 
the water. 

Unclean or cloudy fat is caused by 

1. Insufficient mixing. 

2. Too low speed of tester. 

3. Too low temperature. 

4. Too weak acid. 

Curd particles in fat are caused by 
1. Too weak acid. 



THE BABCOCK TEST 51 

2. Not enough acid. 

3. Too low temperature. 

Cleaning Test Bottles. As soon as the test is read, 
the bottles are emptied by shaking them up and down so 
as to remove the white sediment. Next wash them in 
hot water containing some alkali, and finally rinse them 
with hot water. Occasionally the bottles should be rinsed 
with a special cleaning solution, which is made by dis- 
solving about one ounce of potassium bichromate in one 
pint of sulphuric acid. A small brush should also oc- 
casionally be run up and down the neck of the bottle. 

Reading Cream Tests. Reading the extremes of the 
fat column, as is done in the case of milk tests, gives too 
high a reading. This error is due to the meniscus at the 
top of the fat column, the size of which varies with the 
width of the neck of the bottle. Farrington and Woll 
recommend reading from the lowest extremity of the. fat 
column to the bottom of the meniscus. This is the method 
now commonly employed. Eckles and Wayman recom- 
mend removing the meniscus by adding a small quantity 
of amyl alcohol (colored red) to the top of the fat col- 
umn. This method gives very satisfactory results. 



CHAPTER VI. 

CREAMING. 

Cause. Creaming is due to the difference in the speci- 
fic gravity of the fat and the milk serum. The fat being 
light and insoluble rises, carrying with it some of the 
other constituents of the milk. The result is a layer of 
cream at the surface. 

Processes of Creaming. The processes by which milk 
is creamed may be divided into two general classes : ( I ) 
That in which milk is placed in shallow pans or long 
narrow cans and allowed to set for about twenty-four 
hours, a process known as natural or gravity creaming; 
(2) that in which gravity is aided by subjecting the milk 
to centrifugal force, a process known as centrifugal 
creaming. The centrifugal force has the effect of increas- 
ing the force of gravity many thousands of times, thus 
causing an almost instantaneous creaming. This force 
is generated in the cream separator. 

S'h alio w= Pan Method. The best results with this 
method are secured by straining the milk directly after 
milking into tin pans about twelve inches in diameter 
and two to four inches deep. It is then allowed to remain 
undisturbed at room temperature (6o° to 65 F.) for 
twenty-four to thirty-six hours, after which the cream is 
removed either with a nearly flat, perforated skimmer, or 
by allowing it to glide over the edge of the pan after it 
has been carefully loosened along the sides. The aver- 
age loss of fat in the skim milk by this method is 0.7%. 

52 



CREAMING 



53 




Deep=Cold=Setting Method. The best results with 
this method are secured by using a can like the Cooky 
illustrated in Fig. 18. This can is provided with a cover 
which allows it to be submerged in 
water. It also has a spout at the 
bottom by which the skim milk is 
gently removed, thus preventing the 
partial mixing of cream and skim 
milk incident to skimming with a 
conical dipper. 

The milk is put into the cans di- 
rectly after milking and cooled to 
as low a temperature as possible. 
To secure the best results with this 
method the water should be iced. 
Where this is done the skim milk 
will show only about 0.2% fat. It 
it desirable to allow the milk to set 
twenty-four hours before skimming, though usually the 
creaming is quite complete at the end of twelve or fifteen 
hours. 

Dilution or Aquatic Separators. One of the most 
unsatisfactory methods of creaming is the addition of 
water to the milk. The creaming by this method is done 
in variously constructed tin cans, which the manufacturers 
usually sell under the name of dilution or aquatic sepa- 
rators. Those uninformed about the genuine centrifugal 
separators are often lead to believe that they are buying 
real separators at a low cost when they are investing five, 
ten or fifteen dollars in one of these tin cans, which are 
no more entitled to the term separator than are the com- 
mon shallow pans. The average loss of fat with this 
system of creaming is about ij^%. 



Fig. 18.— Cooley Can. 



54 MARKET DAIRYING 

Centrifugal Method (Hand Separator). Dairies hav- 
ing four or more cows should cream their milk by the cen- 
trifugal method, the hand separator. The saving of but- 
ter fat with this method soon pays for the cost of a sep- 
arator. Moreover it has the additional advantages over 
the gravity methods of creaming in providing fresh, sweet 
skim milk for feeding purposes, and yielding cream of 
any desired richness. 

Efficiency of Creaming With a Separator. Under 
favorable conditions a separator should not leave more 
than .05% fat in the skim milk by the Babcock test 
There are a number of conditions that affect the efficiency 
of skimming and these must be duly considered in making 
a separator test. The following are some of these con- 
ditions : 

A. Speed of bowl. 

B. Steadiness of motion. 

C. Temperature of milk. 

D. Manner of heating milk. 

E. Amount of milk skimmed per hour. 

F. Acidity of milk. 

G. Viscosity of milk. 
H. Richness of cream. 

I. Stage of lactation. (Stripper's milk.) 

A. The greater the speed the more efficient the cream- 
ing, other conditions the same. It is important to see that 
the separator runs at full speed during the separating 
process. 

B. A separator should run as smoothly as a top. The 
slightest trembling will increase the loss of fat in the 
skim milk. Trembling of bowl may be caused by any of 
the following conditions: (1) loose bearings, (2) sepa- 



CREAMING 



rator out of plumb, (3) dirty oil or dirty bearings, (4) un- 
stable foundation, or (5) unbalanced bowl. 

C. The best skimming is not possible with any sepa- 
rator when the temperature falls below 6o° F. A tem- 
perature of 85 ° to 98 F. is the most satisfactory for 
ordinary skimming. Under some conditions the cleanest 
skimming is obtained at tempera- 
tures above ioo° F. The reason 
milk separates better at the higher 
temperatures is that the viscosity is 
reduced. 

D. Sudden heating tends to in- 
crease the loss of fat in skim-milk. 
The reason for this is that the fat 
heats more slowly than the milk 
serum, which diminishes the differ- 
ence between their densities. When, 
for example, milk is suddenly heated 
from near the freezing temperature 
to 85 ° F. by applying live steam, 
the skim-milk may be four times as great as it is under 
favorable conditions. 

E. Unduly crowding a separator increases the loss 
of fat in the skim milk. On the other hand, a marked 
underfeeding is apt to lead to the same result. 

F. The higher the acidity of milk the poorer the 
creaming. With sour milk the loss of fat in the skim 
milk becomes very great. 

G. Sometimes large numbers of undesirable (slimy) 
bacteria find entrance into milk and materially increase 
its viscosity. This results in very unsatisfactory creaming. 
Low temperatures also increase the viscosity of milk 
which accounts for the poor skimming at these tefnpera- 
tures. 




Fig. 19.— Cream Separa- 
tor. 

the loss of fat in 



56 MARKET DAIRYING 

H. Most of the standard makes of separators will do 
satisfactory work when delivering cream of a richness of 
50%. A richer cream is liable to result in a richer skim- 
milk. The reason for this is that in rich cream the skim- 
milk is taken close to the cream line where the skim-milk 
is richest. 

I. Owing to the very small size of the fat globules 
in stripper's milk, such milk is more difficult to cream 
than that produced in the early period of lactation. 

Regulating Richness of Cream. The richness of 
cream is regulated by means of a cream screw in the sepa- 
rator bowl. When a rich cream is desired the screw is 
turned toward the center of the bowl, and for a thin cream 
it is turned away from the center. 

Best Time to Separate Milk. The best results with 
a separator are obtained by running the milk through 
the machine immediately after milking. 

Saving of Butterfat With a Separator. That the 
owner of four good cows can afford to invest $50.00 in a 
small cream separator is shown by the following: Four 
goods cows will yield not less than 24,000 pounds of 
milk a year. By the common shallow pan method of 
creaming, the loss of butterfat will average 0.7 pound 
for every 100 pounds of milk. With the centrifugal sepa- 
rator the loss of fat will not average over 0.05 pound, 
hence there will be effected a saving of 0.65 pound of 
butterfat in each 100 pounds of milk by the use of the 
separator. At this rate, the total saving of butterfat an- 
nually on the 24,000 pounds of milk will be 156 pounds. 
Since each pound of butterfat will yield approximately 
1 1-6 pounds of butter, 183 pounds of butter will be 
saved by the process, which, at 25 cents per pound, 



CREAMING 



57 



amounts to $45.75. This saving in butterfat alone will 
almost pay for the separator in one year. 

Fastening a Separator. To secure steady motion, 
the separator must be fastened to a solid foundation. 
There is nothing- better in this respect than a concrete 
floor, with which every dairy should be provided. 





Fig. 20.— Method of Fastening Separator. 



There are two common methods of fastening a separator 
to a concrete floor : One is to fasten two 4x4-inch blocks 
to the concrete floor as illustrated in Fig. 20. The separa- 
tor is then fastened to these blocks in the same manner 
as to a wood floor. The other method of fastening 
consists in chiseling four conical holes into the concrete 
floor, at a distance corresponding with the four holes in 
the separator base. The cavities thus made are filled with 
babbitt metal, into which holes a little smaller than the lag 
screws are drilled. The separator is then fastened by 
turning the lag screws into the babbitt (Fig. 21). 



58 



MARKET DAIRYING 



The babbitt may be dispensed with by fastening the 
bolts with cement as shown at the left in Fig-. 21. 




Fig. 21. — Methods of Fastening »Separati 



CHAPTER VII. 

STANDARDIZING MILK AND CREAM. 

This is a process by which milk and cream are brought 
to a definite percentage of fat. 

Reducing Milk and Cream with Skim=milk. Cream 
producers are called upon to furnish cream of a definite 
richness, and different grades may be demanded by differ- 
ent buyers. The simplest way to meet such demands is 
to have the separator deliver cream somewhat richer than 
the richest grade called for and to reduce this to the 
required richness by adding skim-milk. 

When a definite quantity of cream of a definite richness 
is to be made up in this way, the following formula will 
be found simple and direct : 

A 
Formula -.-5- X C = D, in which 

A = test desired. 

B = test of original cream. 

C = number of pounds of standardized cream. 

D = number of pounds of original cream. 

Problem: How many pounds each of 45% cream and 

skim-milk (zero test) are required to make 60 pounds 

of 18% cream? 

Substituting in the above formula we have 

18 

— X6o=24=D, the amount of original cream to be 

45 
used. 

The amount of skim-milk always equals C — D. Sub- 

59 



60 MARKET DAIRYING 

stituting for C and D in the above problem we have 60 — 
24 = 36, the amount of skim-milk to be used. 

The same formula may be used to reduce milk to a 
lower percentage of fat by adding skim-milk. 

Enriching Cream and Milk by Extracting Skim= 

milk. If milk and cream are too low in fat, they may 

be made richer by extracting skim-milk according to the 

following formula: 

AXB . 
Formula : X = A — — g- , in which 

X = number of pounds of skim-milk to be extracted. 

A — number of pounds of original milk. 

B = test of original milk. 

C = test desired. 
Problem: How many pounds of skim-milk must be 
extracted from 450 pounds of 4.0% milk to raise the test 
to 4.5%. 

Substituting in the above formula we have 

/450 X 4.0 \ , 

X = 45o— ^ — — J = 50, the 

number of pounds of skim-milk to be extracted. 

The same formula may be used to enrich cream by ex- 
tracting skim-milk. 

Mixing Two Milks or Two Creams, or Milk and 
Cream, of Different Richness. In the preceding two 
formulas the test of the skim-milk was considered zero. 
When milks or creams of different tests are mixed the 
calculation becomes more difficult. Pearson, however, 
has devised a method by which calculations of this kind 
are very much simplified. This method is as follows : 

Draw a rectangle with two diagonals, as shown below. 
At the left hand corners place the tests of the milks or 
creams to be mixed. In the center place the richness 



STANDARDIZING MILK AND CREAM 



61 



desired. At the right hand corners place the differences 
between the two numbers in line with these corners. 
The number at the upper right hand corner represents 
the number of pounds of milk or cream to use with the 
richness indicated in the upper left hand corner. Like- 
wise the number at the lower right hand corner repre- 
sents the number of pounds of milk or cream to use, with 
the richness indicated in the lower left hand corner. 

Example: How many pounds each of 30% cream 
and 3.5% milk required to make 25% cream? 



30% r^zr ~^\ ZL 5 lbs 




3.5 %l^— -^J 5LB5. 



21.5, the difference between 3.5 and 25, is the number 
of pounds of 30% cream needed; and 5, the difference 
between 25 and 30, is the number of pounds of 3.5% 
milk needed. 

From the ratio of milk and cream thus found, any 
definite quantity is easily made up. If, for example, 300 
pounds of 25% cream is desired, the number of pounds 
each of 30% cream and 3.5% milk is determined as fol- 
lows: 

21.5 + 5 = 26.5 

21.5 

' 300 = 243.4, the number of pounds 

of 30% cream. 



26.5 

5 
26.5 



X 300 = 56.6, the number of pounds 

of 3.5% milk. 



CHAPTER VIII. 



COLD STORAGE. 



Cold storage of some kind is indispensable to a well 
equipped dairy. Many, however, lack this essential, either 
because they do not appreciate its importance, or be- 
cause of the rather high price of commercial refrigerators. 

The value of low temperature in keeping milk sweet 
has frequently been shown by experimental data and is 
again shown here by the results of a large number of 
experiments recently conducted by the author. The aver- 
age results secured in twenty-six experiments show that 
milk cooled to 45 ° F. one hour after milking contained 
0.19 per cent acid; the same milk kept in the refrigerator 
at a temperature of 44 ° F. for fifteen hours showed 0.20 
per cent acid, an increase of only 0.01 per cent. In 
another series of ten experiments milk cooled to 45 ° F. 
one hour after milking showed an average of 0.19 per 
cent acid ; the same milk kept in the refrigerator at a 
temperature of 44 F. for twenty-four hours showed an 
average of 0.21 per cent acid, an increase of only 0.02 
per cent. 

These results show that there is practically no develop- 
ment of acid in milk kept at a temperature of 44 F. 
("Bui. No. 198, N. C. Exp. Sta.) 

Ice Box for Small Dairymen. A simple, cheap and 
effective ice box that will answer the purpose of a refrig- 
erator for small dairymen has recently been constructed 

62 



COLD STORAGE 



63 



by the author. A detailed description of this box, to- 
gether with a cross-sectional cut of the same, is herewith 




Fig. 22. — Cross-Section of Ice Box. 

presented. The dimensions given will answer for a dairy 
of twenty cows. 

The construction of this box, as shown in Fig. 22, con- 
sists essentially of two boxes separated by one-inch strips 



64 MARKET DAIRYING 

placed at intervals of about one foot. Double thickness 
of building paper is placed on both sides of the strips 
and tacked to the boxes. A one-inch strip, two inches 
wide, covers the upper space between the one-inch strips, 
thus making a dead-air space between the two boxes. 
The construction of the cover is the same as that of the 
bottom, with the exception that there is a flange at the 
front and sides of the cover. 

The sides, bottom and cover of the refrigerator are built 
of three-quarter-inch tongued and grooved lumber, five 
and a half inches wide. The ends are constructed of 
one and one-eighth inch tongued and grooved flooring 
three and a half inches wide. The inside of the ice box 
is lined with galvanized iron. To insure tightness, a 
layer of felt is tacked around the box and cover where 
the two meet. The four vertical edges of the box 
are tightened and strengthened by tacking over each 
a double layer of paper, which is covered with two 6-inch 
boards. 

A heavy weight attached to a one-half inch rope, run- 
ning over a pulley fastened to the ceiling, raises the 
cover and holds it open when desired. A short piece 
of rope with a hook attached is used to counterbalance 
the weight by hooking to the front of the box, thus allow- 
ing the full weight of the cover to rest on the box. 

A short piece of one-half inch gas pipe is inserted 
through the bottom of the box to provide drainage, the 
outlet of this pipe being connected with a trap to prevent 
entrance of air into the box. 

The entire construction of the ice box is so simple that 
any one with a little knowledge of carpentry can readily 
build it. 



COLD STORAGE 65 

The inside dimensions are: Length, 7 1-3 feet; width, 
2 1-4 feet; depth, 21-3 feet. 

An itemized statement of the cost of it is as follows : 

200 ft. ?4" x $y 2 " — 16' tongued and grooved lumber $4.00 

54 ft. i]4," x 314" — 16' tongued and grooved lumber 2.16 

168 ft. 1" x 1" — 12' strips 1.26 

4 hinges 60 

Yi yard felt 63 

15 ft. ^-inch rope 30 

2 strong hooks 10 

1 2-inch iron pulley 50 

Carpentry work, 3 days 6.00 

Complete lining with galvanized iron 11.25 

500 sq. ft. building paper 60 

Total cost $27.40 

A test of this ice box for six days with an average of 
200 pounds of ice in the box showed that an average tem- 
perature of 39 F. was maintained within it, with an 
average daily consumption of 40^ pounds of ice, while 
the temperature of the room in which the ice box was 
kept averaged 74 ° F. 

When twenty-two gallons of milk, which had been 
cooled to 45 F., were stored in the box eight hours 
daily with the other conditions as above, the average 
daily ice consumption for six days was 49 pounds, and 
the average temperature of the box 40 F. 

An additional air space could be secured at a small 
increased expense, and this would not only save ice, 
but would also make it possible to maintain a somewhat 
lower temperature than that above indicated. 

Refrigerator for Large Dairies. For large dairies a 

refrigerator like that illustrated in Fig 23 (original), will 

be found very satisfactory. The entire inside is finished 

with concrete making it both durable and sanitary. Two 

5 



66 



MARKET DAIRYING 




H 5ULAT IOH( A5BE5TQ5, MOlt-OW BRICK OR TlLE) 






Fig. 23.— Showing Refrigerator and Construction of Dairy House. # 



COLD STORAGE 67 

dead air spaces are provided: a three-quarter-inch space 
between the concrete and the boards to which the wire 
lathing is fastened and a four-inch space between the 
2x4-inch studding. These two spaces together with the 
four layers of paper used, provide a high degree of insula- 
tion. 

The concrete floor of the refrigerator is constructed 
upon twelve inches of cinders overlaid with asbestos, both 
of which materials act as insulators. (See page 133.) 

The floor of the ice chamber is built of 2x4~inch stud- 
ding running the length of the refrigerator. These studs 
are laid about three inches apart to allow the water from 
the melting ice to drip through. Below the ice chamber 
is a shallow pan, which catches the drip from the ice 
and conducts it either into the sewer or into a cooling 
tank. The pan is supported by means of two 2x4-inch 
studs running the full length of the ice chamber. Both 
ends of the studs are provided with hooks, by means of 
which the pan is readily attached to, and detached from, 
the ice chamber. This method of attachment is necessary 
to permit the easy removal of the pan for cleaning. 

Where a refrigerator of this style is used it is pref- 
erably located in the corner occupied by the ice box as 
shown in the floor plan of the dairy house (Fig. 56, page 
131). The rear of the refrigerator is built into the wall of 
the dairy house in the same way as the side shown in 
Fig. 23. 

The refrigerator must be provided with a door having 
at least two dead-air spaces and two flanges which fit 
snugly into the frame of the refrigerator. 

The ice is admitted to the ice chamber through a door 
in the front end of the refrigerator. 

Refrigerator Cooled with Ammonia. Such a re- 



68 



MARKET DAIRYING 



frigerator may be constructed in the same way as the 
one described in the preceding pages, with the exception 
of the ice chamber. In place of this a brine tank and 
refrigerator coils are used as shown in Fig. 59, page 137. 
For further particulars regarding this method or refrig- 
eration, see chapter on Mechanical Refrigeration. 




Section through Refrigerator Having Ice Chamber at One End. 



CHAPTER IX. 

HOW TO SECURE A GOOD MARKET. 

Quality. As a rule it is easy enough to secure some 
kind of a market, but to secure the best frequently re- 
quires considerable effort. To get fancy prices requires 
first of all that the product be of superior quality. This 
is particularly true of milk. The extensive agitation in 
recent years for clean, pure milk has had the effect of 
putting a high premium upon such milk. The public is 
becoming aware of the dangers which lurk in dirty, un- 
sanitary milk and is willing to pay a good price for milk 
whose wholesomeness is unquestioned. 

Value of Advertising. To obtain big prices it is not 
enough to have products of superior quality, but what- 
ever particular merits they have must be forcibly brought 
to the attention of consumers. In other words, a certain 
amount of advertising is necessary. 

It is good policy to furnish prospective customers a 
few free samples and to distribute leaflets describing the 
conditions under which the products are produced and 
handled. If the milk is produced in clean, ventilated, 
whitewashed stables, and from cows which are regularly 
tested for tuberculosis ; if the milk is handled by clean, 
healthy attendants and is thoroughly cooled and aerated 
immediately after milking; and if, in addition, all this 
is certified to by a competent inspector, an increase in 
prices and patronage is certain to follow when such facts 
are placed before the public. 

69 



70 MARKET DAIRYING 

The majority of city consumers have little conception 
of the conditions under which average milk is produced. 
For this reason the man who is producing clean milk will 
find it highly profitable to place in contrast vivid pictures 
of the conditions that yield average milk and those that 
yield sanitary milk. 

Investigate Outside Markets. Often outside mark- 
ets offer better prices for milk and cream than does the 
home market. This is especially true of cream. This 
product permits of long distance shipping and many out- 
side markets may be glad to get it at fancy prices when 
the home market may be entirely overstocked. 

Dairymen must not expect the market to come to them, 
however ; they must seek the market. A visit or corre- 
spondence with managers of cafes, hotels, restaurants, 
drug stores and ice cream manufactories in different 
cities, is frequently the means of securing more business 
and better prices. 

Where one is just starting in the dairy business or 
trying new markets, it is good policy, as a rule, not to 
ask very high prices at the start. First demonstrate the 
merits of your products. If these are of a high order 
consumers will gradually respond to demands for in- 
creased prices rather than lose the products. Too high 
prices at the start are likely to discourage prospective 
buyers, and thus deprive you of an opportunity to prove 
the value of your goods. 

Uniformity; One of the essentials in building up a 
good market is uniformity of product. Where this is 
lacking, improvements in other directions will be of little 
avail. On the other hand, products which are uniformly 
the same, week after week, and month after month, are 



TO SECURE A GOOD MARKET 71 

likely to command good prices even when of only medium 
quality. 

Punctuality. Another essential in building up a good 
market is punctuality. If your customer expects his milk 
at 7:30, do not deliver it at 7:40; deliver early rather 
than late. If you are shipping cream or milk you cannot 
afford to miss your train — even a single time. It gen- 
erally means greater disappointment at the other end of 
the line than one would anticipate. 

Try to Please. Always put yourself in an attitude 
to please. If criticisms come concerning your products, 
you cannot afford to resent them. Usually there is reason 
for the criticism. Try to discover the trouble and remedy 
it. 

Delivery Outfit. Cleanliness and neatness must char- 
acterize the dairy business throughout. Milk wagons, 
cans, bottles, drivers, etc., must present a clean appear- 
ance. Where they do not, it is usually an easy matter 
to surmise the condition of milk. 

Use a Trade Mark.- The name or monogram of the 
dairy, placed upon the products and delivery wagons, 
guarantees genuineness and will materially assist in se- 
curing a better and more extended market. It is one 
of the best ways of advertising a superior product. 

Secure Your Market Early. If it is intended to sell 
cream for manufacture into ice cream, it is important 
to get a market early in the spring. It is difficult to find 
one in the flush of the ice cream season, because ice cream 
dealers, as a rule, contract considerably in advance of 
the time they need the cream. If it is intended to supply 
winter resorts, apply for the market early in the fall. 
What has been said here with reference to cream applies 
also to milk. 



72 MARKET DAIRYING 

Secure Reliable Customers. Where milk and cream 
are shipped some distance, it is important to determine 
beforehand the reliability of the buyer. As a rule it 
is good policy not to make more than three shipments 
before the first has been paid for. It is well, even where 
milk and cream are sold locally, to investigate the stand- 
ings of customers before their accounts have run up very 
high. 

Selling Direct to Consumers. No argument is need- 
ed to show the advantage of selling dairy products direct 
to consumers wherever this is possible. It means the 
elimination of the middleman whose profits are saved to 
the dairyman. 

Letterhead Stationery. It is not only businesslike 
to use stationery with a suitable letterhead, but it also 
serves to advertise the business. The following is sub- 
mitted as a suitable form of letterhead : 

Springdale Sanitary Dairy. 

J. C. Boone, Prop. 

Dealer in 

Pure, Bottled, Jersey Milk and Cream 

from Tuberculin Tested Cows. 
Reidsville, N. H 190. . 



CHAPTER X. 



RETAILING MILK AND CREAM. 



Dip Method. The old method of hauling milk to the 
city in five, eight or ten gallon cans and removing each 
patron's allowance by means of a dipper or faucet, has 
been found so objectionable that the practice has been 
largely abandoned. The principal objections to this 
method are : ( i ) The admission of 
dust and bacteria to the milk while 
measuring it; (2) the use of unsteri- 
lized milk vessels by consumers; (3) 
exposure of the vessels to dust while 
on the steps of the consumer; (4) the 
use of unclean vessels by milkmen in 
measuring each customer's share ; ( 5 ) 
lack of uniformity in the milk, espe- 
cially if removed from the cans by 
means of a faucet, in which case the 
first drawn milk is likely to be lowest 
in fat content; and (6) the possi- 
bility of drivers tampering with the 
milk. 

The Use of Bottles. Milk and cream intended for re- 
tail trade should be put into pint or quart bottles, like 
that shown in Fig. 24. The advantages of this method 
are apparent from the fact that the milk is bot- 
tled immediately after cooling and that it may be 




T HlS BOTTLE 
To BE WASHES 
IN RETURN^, 



Fig. 24.— Milk Bottle. 



73 



74 MARKET DAIRYING 

kept in the same bottle until it is to be consumed. 
Whenever milk is changed from one vessel to another 
there is always more or less contamination from dust and 
bacteria. 

Bottling.- For dairies having from ten to twenty 
cows, a can or vat provided with a sanitary faucet will 
do satisfactory work in filling bottles. A pouring can 
with a slightly curved spout may also be used for this 
purpose. 




Fig. 25.— Filling Bottles with Machine. (From Da. Div., U. S. Dept. of A.) 

For large dairies a bottle filler like that shown in Fig. 
25 will be found advantageous. This machine fills six 
bottles at the same time. Larger or smaller fillers may be 
had if desired. In selecting a bottle filler secure one of 
simplest construction and preferably without rubber at- 
tachments. This is important for sanitary reasons. 

Whatever method of filling is used, it is important to 
keep the milk well stirred while filling, so as to insure 
uniform quality in all the bottles. 



RETAILING MILK AND CREAM 



75 



Immediately after filling, the bottles should be capped 
with paraffined caps made for this purpose. Fig. 
26 illustrates a cap provided with a little handle which 
facilitates its removal 
and leaves it intact. 

During bottling the 
room should be kept 
damp to keep the air 
free from dust and 
bacteria. No air cur- 
rent should be al- 
lowed to sweep in 
from the outside. 
Only clean laundered 
white suits should be 
worn by those in 

Charge of the COOling Fig. 26.- Bottle Cap with Handle. 

and bottling. 

Milk Bottle Delivery Cases. On delivery wagons 
the bottles are carried in cases holding twelve or more 





Fig. 27.— Galvanized Iron Milk Bottle Case. 



bottles each. These cases are made of galvanized iron 
or wood, or of both, and have light removable partitions 
inside, separating the bottles to keep them from breaking. 
Galvanized iron cases, like that shown in Fig. 2j, are 



76 MARKET DAIRYING 

the most sanitary and also permit putting crushed ice 
around the bottles. 

Fig. 28 shows a galvanized iron milk bottle case, 
enclosed by a box made of one-inch boards and pro- 
vided with a tight fitting cover. Cases of this kind should 
be used in warm weather to keep the milk cool during 




Fig. 28.— Insulated Galvanized Iron Milk Bottle 
Case. 

delivery. On especially warm days, crushed ice should 
be used around the bottles. This style of case is also 
recommended where bottles are shipped. 

A great deal of milk is spoiled while in transit to the 
consumer. The last milk delivered on the route may 
be on the road five or six hours before it finally 
reaches its destination. If carried in open, uniced cases, 
on warm days, an exposure of such duration may easily 
shorten the keeping quality of the milk by eight or more 
hours. 

A matter of prime importance in delivering milk in 
bottles is to have them thoroughly sterilized before using. 
Unless this is done milk will not keep long and, what is 
worse, is likely to disseminate disease along the route. 



RETAILING MILK AND CREAM 77 

This danger is due to the bottles' passing from one home 
to another and eventually reaching a home in which there 
is some cantagious disease. In such cases there is always 
a probability that the bottles may become infected with 
the disease germs. 

Frequency of Delivering Milk. When milk is cooled 
to 45 F. or below immediately after milking and is 
held at this temperature until it reaches the consumer, one 
delivery a day is sufficient. If it is desirable, however, 
to make two deliveries a day, these should be made inde- 
pendent of the milking; that is, the night's milk should 
be delivered in the morning and the morning's milk in 
the afternoon. 

In some sections, especially in the south, milk is sold 
with little or no cooling whatever. Hence, the practice 
of delivering the morning's milk before breakfast, and 
the night's milk before supper. This practice requires 
the first milking to be done shortly after midnight and 
the second milking shortly after midday, a drudgery 
wholly unnecessary and easily obviated by thoroughly 
cooling the milk. 

Delivery Wagons. These should be clean, covered, 
well painted, and provided with good springs. The name 
of the dairy should be printed on each side. A neat and at- 
tractive delivery wagon is essential in building up a good 
trade. 



CHAPTER XL 

SHIPPING MILK AND CREAM. 

The essential things in shipping milk and cream are 
cleanliness and low temperature. It is possible to keep 
milk and cream in good condition for two or three days, 
if produced and handled under cleanly conditions and 





Fig. 29. Milk Can. 



Fig. 30.— Felt Jacket on Can. 



cooled directly after milking to 40 F. or below. This 
low temperature must be maintained when long keeping 
quality is desired. Every dairy should be provided with 
a good ice box or refrigerator, into which milk and cream 

78 



SHIPPING MILK AND CREAM 



79 



may be placed immediately after cooling and in which 
they may be kept until ready for shipment. 

Shipping in Cans. Various insulated cans are now 
upon the market and a number of these have been tested 
by the author. The tests showed that these cans possess 
about the same insulating effect as the felt jackets that 
are commonly 
wrapped around ordi- 
nary milk cans. Since 
the latter, as a rule, 
are more durable and 
more easily handled, 
they will be found 
more satisfactory 
when wrapped with a 
felt jacket than the so- 
called insulated ship- 
ping cans. 

When milk and 
cream are cooled close 
to freezing and placed 
in ordinary milk cans 
wrapped in felt jack- 
ets, they may be safe- 
ly shipped to any 
point that may be 
reached within 
24 hours even 
i n warm weather. 
If the temperature of the milk and cream at the time of 
shipment is 50 F. or higher, then long distance ship- 
ment is best accomplished by the use of an ordinary can 
placed inside of a covered ice cream shipping tub con- 
taining ice. Such a tub has practically the same in- 




Fig. 31.— Screw Top Can. 



80 MARKET DAIRYING 

sulating effect as a felt jacket, but is rather heavy and 
cumbersome and should not be used except in cases where 
it is necessary to pack ice around the cream or milk. The 
best results from the ice are secured by packing it in 
large lumps around the neck of the can. 

Shipping in Bottles. Where milk and cream are 
shipped in bottles, the latter should be placed in insulated 
delivery cases (Fig. 28) and surrounded with crushed 
ice. The cases should have the owner's address on them 
and must be kept locked while in transit. 

Mode of Shipping. The usual way of shipping milk 
and cream is by express. In the main dairy sections bag- 
gage rates are available. These rates are lower than ex- 
press rates and can be obtained nearly everywhere by 
special arrangement with the railroad companies. 

Shipping rates should always be obtained in advance 
of shipment and the charges should be prepaid. A con- 
siderable saving is certain to be effected by rigidly ad- 
hering to this practice. Insist upon getting the lowest 
rates possible. 

Pointers on Shipping. Have the name and address 
of your dairy permanently marked in brass upon every 
can and cover ; also have it sewed or stitched on the felt 
jackets. This is necessary to insure the return of your 
own goods. The name and address will be put upon the 
cans and covers by the dealer from whom they are pur- 
chased, if so requested ; or, in case unmarked cans are 
already on the premises, the brass plates with the name 
and address may be purchased from dairy supply firms 
and placed upon the cans and covers by a local tinner. 

Even when labeled as indicated above, cans will oc- 
casionally get lost. Empty cans are usually returned free 
of charge and, for this reason, express receipts are com- 



SHIPPING MILK AND CREAM 81 

monly not taken for them. This is a mistake. If the 
purchaser of your products will take a receipt for the 
empty cans, th^ express company becomes responsible for 
them in the event they are lost. Without the receipt it 
is next to impossible to claim damages for lost goods. 

The empty cans should be washed before they are re- 
turned. This rhould be done for sanitary reasons as well 
as for the protection of the cans, which are short-lived 
unless washed and dried immediately after use. 

Another matter of importance in shipping is to have 
the cans full to prevent churning. 




Fig. 32.— Lead Seal and Seal Press. 

It is necessary also to have the cans sealed to prevent 
tampering with the contents. The sealing is easily accom- 
plished by means of lead seals and a seal press (Fig. 32). 

In delivering the cream or milk at the station the de- 
livery man should see to it that the cans are put in as 
cool a place as possible. 



CHAPTER XII. 

WASHING AND STERILIZING MILK VESSELS. 

Wash Sinks. A matter of importance in washing 
milk vessels is to have the right kind of sinks, three of 
which are needed for the most satisfactory work: One 




Fig. 33— Wash Sinks. 

for rinsing before washing, one for washing and one for 
final rinsing. 

For convenience the wash sink should be thirty-six 

82 



WASHING AND STERILIZING 



83 



inches long, twelve inches deep, and sixteen inches wide. 
The bottom should be round and two feet from the floor. 
When closer to the floor than this too much stooping is 
required. 




Fig. 35.— Milk Bottle Brush. 
Fig. 34.— A Good Cleaning Brush. 

Galvanized iron furnishes one of the most suitable ma- 
terials for the construction* of wash sinks. They should 
be provided with steam and cold water pipes as shown 
in Fig. 33. 

Method of Washing. All vessels should be thor- 
oughly rinsed in 
warm water to re- 
move small residues 
of milk and cream. 
The rinsing is fol- 
lowed by washing 
with moderately hot 
water to which a 
handful of some 
cleaning powder has 
been added. The 
washing should be 
done with brushes 
rather than cloths be- 
cause the bristles en- 
ter into crevices which 
a cloth could not possibly reach. Finally rinse the vessels 
in clean water. 

A bottle washer, like that shown in Fig. 36, saves much 




Fig. 36.— Bottle Washer. 



84 



MARKET DAIRYING 



labor and does very efficient work. The motive power 
may be either steam or water. 

Sterilizing. Vessels that have been washed in the man- 
ner described above may look perfectly clean, but may 
still be far from being free from bacteria. These can be 
destroyed only by exposing the vessels to the boiling 
temperature for some time. 




Fig. 37.— Cheap Arrangement for Securing Hot Water. 

The simplest method of sterilizing is to place the vessels 
in boiling water for five minutes. This method com- 
mends itself especially to small dairymen who have no 
steam. 

Where no steam is available, the best means of pro- 
curing hot water is the apparatus shown in Fig. 37. 

The hot water tank is that commonly used in residences 
for heating water for the bath tub and can be obtained 



WASHING AND STERILIZING 



85 




Fig. 38.— Sterilizing Truck and Front of Brick Sterilizer. 

from plumbers for about $7.00. Any stove in which 
iron coils can be heated will answer as a heater. 

The best method of sterilizing is to place the vessels 



86 



MARKET DAIRYING 



in a steam chamber of sufficient strength to withstand a 
pressure of ten or more pounds to the square inch. These 
sterilizers are usually constructed of concrete or brick and 




Fig. 39.— Cross-Section of Concrete Sterilizer. 

are provided with a heavy iron door which is large enough 

to admit a truck bearing the pails, cans, bottles, etc. Other 

sterilizers of this type are constructed of galvanized iron. 

The principal drawback to some of these sterilizers is 



WASHING AND STERILIZING 87 

their high cost, which renders their use by small dairy- 
men almost prohibitive. 

Sterilizer Designed by the Author. After consid- 
erable study and experimentation, the author succeeded 
in constructing a simple and efficient concrete sterilizer 
whose low cost puts it within reach of all dairymen. A 
section through this sterilizer is shown in Fig. 39. 

Essentially, it is a rectangular concrete tank with a 
wooden cover which is lined with zinc. The sides and 
bottom are five inches thick and are built of concrete, 
which is made up of one part cement, two parts sand, 
and two parts coarse gravel. A thin coat, consisting 
of one part cement and two parts sand, is used as an 
inside finish. A piece of 2x4~inch studding is placed 
around the top of the tank and is secured by six one-half- 
inch iron rods two feet long, embedded in the concrete 
walls, one being placed at each corner and one on either 
side midway between the corners. This arrangement not 
only strengthens the tank, but also makes the cover fit 
tighter. 

The cover consists of two thicknesses of one and one- 
eighth-inch tongued and grooved flooring three and one- 
half inches wide. The upper boards run lengthwise and 
the lower crosswise of the tank. The lower boards fit 
into a shoulder projecting from the base of the 2x4-inch 
studding. The entire inside portion of the cover is cov- 
ered w T ith zinc. To insure additional tightness of the 
cover, a layer of asbestos is placed on top of the 2x4s. 
A heavy weight attached to a one-half inch rope running 
over a pulley fastened to the ceiling, raises the cover and 
holds it open when desired. The cover is strengthened 
by running three pieces of 2x4-inch studding cross-wise 
of the tank, one at the middle and one at either end. The 



88 MARKET DAIRYING 

hinges by which the cover is fastened are attached to 
these 2x4s, as shown in Fig. 39. 

A safety valve, set at ten pounds pressure, is inserted 
through the top of the cover at the most convenient place. 
A bell trap (see Fig. 58) placed in the bottom of the 
sterilizer serves as an outlet for the condensed steam. 

The steam is admitted either through the sides or 
through the bottom of the sterilizer, and both inlet and 
outlet pipes should be laid in the concrete at the time the 
sterilizer is being built. 

A false, perforated, metallic bottom is placed one inch 
from the bottom of the sterilizer, on which all vessels are 
placed in an inverted position. 

The following is an itemized statement of the cost of 
the material used in the construction of this sterilizer, 
.whose inside dimensions are: length, 71-3 feet; width, 
2 1-4 feet; depth, 2 1-3 feet. 



2 bbls. of Portland cement •. $5.20 

20 ft. of 2x4 studding. 30 

no ft. of 1% tongue and grooved flooring, s l A wide 4.40 

4 hinges 40 

5 lbs. nails 20 

6 ^-inch iron rods 2^2 feet long 1.20 

3 hasps . 30 

20 sq. ft. zinc 1.75 

Ball and lever safety-valve 1.00 

3 pounds sheet asbestos 30 

Total .$1505 

Sterilizing Bottles. The most convenient way to 
sterilize bottles is to place them in metallic cases like 
that shown in Fig. 40. A reversing rack is placed over 
the cases, which permits sterilizing the bottles in an in- 
verted position. 

Importance of Keeping Vessels Inverted. It is not 



WASHING AND STERILIZING 



89 



enough to keep cans, bottles, pails, etc., inverted during 
sterilization, they should be kept inverted until ready to 
use. This insures perfect drainage and keeps out dust 
and bacteria. 



Fig. 40. -Crate for Sterilizing Bottles. 

Where hot water is used for sterilizing, the vessels 
should be inverted on perforated metallic shelves as soon 
as removed from the water. 

Steam Jet. In sterilizing with a steam jet, the vessels 
are inverted over the end of a steam pipe and steamed 
for a number of minutes. Though commonly used in the 
past, the steam jet is much less efficient than either hot 
water or steam used under pressure in a sterilizer. 



CHAPTER XIII. 

MAKING AND MARKETING COTTAGE CHEESE. 
(Also called curd cheese, smear kase, Dutch cheese, etc.) 

In making cottage cheese the first and most important 
essential is good flavor. Next in importance is uniformity 
of product. Both of these essentials can be obtained with 
certainty only by the use of pure cultures of lactic acid 
bacteria in souring the skim-milk. 

The natural souring of milk is due to lactic acid bac- 
teria. Milk always contains these souring organisms, but 
as a rule, there are present also various other types which 
produce undesirable flavors. To suppress the undesirable 
types it is necessary to reinforce the lactic acid organ- 
isms by adding large quantities of them in pure form, 
that is, unmixed with other classes of bacteria. In com- 
mon parlance such pure cultures of lactic acid bacteria 
are known as "starters." 

METHOD OE USING PURE CULTURES. 

The original cultures containing the lactic acid bacteria 
are prepared commercially and small samples, either 
in dry or liquid form, can be obtained from the manu- 
facturers at about 75 cents per bottle. The bottle thus 
obtained is emptied into a quart of pasteurized skim-milk, 
that is, skim-milk which has been kept at a temperature 
of about 160 F. for 30 minutes and is then quickly cooled 
to about yo° F. As soon as the quart of skim-milk has 

90 



COTTAGE CHEESE 91 

thickened, which usually requires about 24 hours, it is 
ready for use. 

In the heating process all of the active bacteria in the 
skim-milk have been destroyed, thus leaving a clean field 
for the development of the lactic acid bacteria added to 
it from the bottle. 

The method of using the lactic acid bacteria is similar 
to the use of yeast germs in bread making. The original 
germs obtained from the manufacturer may be propagated 
for weeks by daily transferring a small amount of the 
thickened skim-milk to newly pasteurized skim-milk. As 
a rule, one pound of the thickened skim-milk will sour 
from 30 to 40 pounds of sweet pasteurized skim-milk in 
24 hours at a temperature of 70 F. 

When ordering a bottle of culture, ask the manufac- 
turer for full directions for use and follow the directions 
as closely as possible. 

PROCESS OF MAKING COTTAGE CHEESE. 

Hitherto no definite method has been employed in the 
making of cottage cheese which, no doubt, is largely due 
to the fact that its manufacture has been almost entirely 
confined to the home. The method in common use con- 
sists essentially in placing curdled milk, either heated or 
unheated, in a linen or cotton bag which is hung up in 
some convenient place to allow the curd to drain. 

Where cheese is to be made on a commercial scale, this 
method has not been found satisfactory. After much 
experimentation the author has succeeded in developing 
a method which has proven very successful in making 
cheese for city trade. The successive steps in this process 
are fully treated in the following paragraphs. 



92 MARKET DAIRYING 

Souring the Skim=milk. Where from ten to twenty 
pounds of cheese are to be made at one time, the skim- 
milk is most satisfactorily soured in four to eight gallon 




Fig. 41.— Method of Heating Cottage Cheese. Curd Strainer. 

shot gun cans, which have a uniform diameter of from 
eight to ten inches. Enough pure culture of lactic acid 
bacteria is added to sour the skim-milk in about four 
hours at a temperature of ioo° F. As a rule one gallon 



COTTAGE CHEESE 93 

of culture to every four gallons of sweet skim-milk will 
accomplish the souring in the given time. 

The culture should be vigorously stirred and then thor- 
oughly mixed with the skim-milk. As soon as this has 
been done the cans containing the mixture are placed in 
a tank of water as shown in Fig. 41. In heating the 
skim-milk to ioo° F. the water in the tank should at no 
time exceed no° F. The high temperature employed in 
souring the skim-milk has several advantages : ( 1 ) It 
hastens the souring process; (2) it causes the skim-milk 
to curdle with less acid, thus making a milder cheese ; 
and (3) the curd may be stirred at once without danger 
of diminishing the yield. 

Where large quantities of cheese are to be made, the 
skim-milk should be soured in a common milk, cream or 
cheese vat. 

Heating the Curd. As soon as the skim-milk has thor- 
oughly curdled, the curd should be raised to a temperature 
of 104 F. by heating the water surrounding it to about 
1 1 5° F. and care should be taken never, to heat the water 
above 120 F. During the heating process the curd 
should be constantly stirred with a stirrer consisting of a 
four-inch heavy tin disc attached to an iron rod. Where 
a vat is used, the stirring is done by hand. When 
the curd has reached a temperature of 104 F. the water 
surrounding it should be removed and the stirring con- 
tinued for about ten more minutes when it is ready to 
drain. 

Draining the Curd. This is best accomplished in a 
tin strainer with perforated sides and bottom like that 
shown in Figs. 41 and 42. The strainer should be of 
ample size to conveniently hold the curd and to expedite 
drainage. A piece of cheese cloth should be spread over 



94 MARKET DAIRYING 

the strainer before receiving the curd which must be 
hand stirred as soon as it reaches the strainer; but the 
stirring must be done very carefully at the start to avoid 
loss by mashing the particles. 

The stirring should be continued until the curd is firm 
enough to prevent the particles from sticking together, 
which usually requires about five minutes. When the 
proper firmness is reached, it is wrapped in the cloth 




Fig. 42.— Grinding Cottage Cheese. Curd Strainer with Curd. 

strainer and squeezed with the hands until most of the 
whey has been removed. This operation requires only 
a few minutes, and care must be taken not to press the 
curd too hard. After pressing, the curd appears in a 
roll like that shown in Fig. 42. 

Grinding the Curd. Immediately after pressing, the 
curd is run through an ordinary meat grinder, like that 
shown in Fig. 42. The machine should be set for coarse 
grinding and should be large enough to enable one to 
complete the grinding in a few minutes. 

Salting and Adding Sweet Milk. The curd is pref- 
erably ground into a tin pan, in which it is salted and 



COTTAGE CHEESE 95 

treated with sweet whole milk of good quality. Salt is 
applied at the rate of one ounce for every ten gallons of 
skim-milk used. It is best to salt lightly, leaving it to 
the consumer to supply any deficiency. The curd is 
treated with milk at the rate of one and one-half to two 
quarts for every ten gallons of skim-milk used. Two- 
thirds of this is added immediately after grinding, after 
which the curd is set aside for about two hours, preferably 
in the refrigerator. This amount of time is necessary 




Fig. 43.— Cottage Cheese Packages. Method of Filling Packages. 

to permit thorough absorption of the milk. The remain- 
ing third of the milk is then added, the curd thoroughly 
mixed, and immediately packed. 

The amount of milk to be added to the curd varies 
somewhat from day to day, depending upon the amount 
of moisture left in it at the time of grinding. The rule 
to follow is to add enough milk to leave the curd fairly 
wet, but not so wet as to have the milk drip from it. 

Packages and Packing. Among a number of styles 
of packages tried, two have proven very satisfactory ; 



96 MARKET DAIRYING 

namely, the Gem Fibre butter package, made of paste- 
board and lined with parchment paper ; and a water-proof 
paper package commonly used for carrying ice cream. 
Both of these packages are illustrated in Fig. 43. The 
round packages are the Gem Fibre, which are easier to 
pack and better liked by consumers, though they cost 
somewhat more than the water-proof paper sacks. It was 
found best to line both packages with parchment paper 
(iixii inches) which had been thoroughly soaked in salt 
brine. Any surplus moisture should be allowed to drip 
from the paper before putting it into the packages. The 
latter must also be rinsed in clean water before using, 
to insure freedom from dust. 

The cheese is put into the packages by means of a 
large spoon, in the manner shown in Fig. 43. One pound 
packages appear to be the most satisfactory for the aver- 
age trade. 

Yield of Cheese. The average amount of skim-milk 
required to make a pound of cheese was 7.1 pounds. 

Marketing Cottage Cheese. The author has sold 
large quantities of this cheese to grocers at ten cents per 
pound, the latter retailing the same at fifteen cents per 
pound. The grocers were supplied with attractive signs 
calling attention to the fact that the product was for 
sale by them. The local press was also used to set forth 
the nutritive and wholesome qualities of the cheese. Free 
samples may also be advantageously distributed among 
prospective customers. 

Cottage cheese should be kept at a low temperature 
from the time it is made until it is consumed. At re- 
frigerator temperature, it may be kept in good condi- 
tion for several days. The most satisfactory way of 
disposing of cottage cheese is to sell it direct to the milk 



COTTAGE CHEESE 97 

and cream customers along- the route daily traveled by 
the dairyman. This saves the middleman's profits and 
insures the delivery of the product fresh every day. 

How to Serve Cottage Cheese. When the cheese is 
made according to the author's method, it may be served 
without any further treatment. Its palatability, however, 
may be improved by the addition of cream. Additional 
salt and some pepper is also preferred by some. Others 
prefer adding sugar or syrup. Caraway and sage are 
sometimes used to flavor the cheese. 

Cottage Cheese as a Food. Cottage cheese when 
made as herein described, not only has a high food value, 
but also has tonic or medical qualities which are especially 
commendable during warm weather. Its nutritive value 
is nearly the same as that of beefsteak. 

7 



CHAPTER XIV. 

MAKING AND MARKETING SKIMMILK-BUTT^RMILK. 

Souring the Skim=milk. As soon as the skim-milk 
leaves the separator, whole milk is added at the rate of 
one gallon to twenty gallons of skim-milk. This gives the 
mixture a fat content, which approximates that of ordinary 
buttermilk. A large quantity of pure culture of lactic 
acid bacteria (starter, see p. 90) is next added and the 
temperature brought to 70 F. Enough starter is added to 
curdle the skim-milk in about six hours at the temperature 
mentioned. This requires about one pound of culture for 
every three pounds of skim-milk. When a temperature 
above 70 E. is employed, there is a tendency for whey 
to separate after the skim-milk has curdled. 

Churning. When thoroughly curdled, the skim-milk 
is placed in a churn and churned for about thirty minutes 
in the same way that cream is churned in making butter. 
The churning process thoroughly breaks up the curd clots, 
resulting in a smooth, thick liquid which cannot be dis- 
tinguished from ordinary good buttermilk. 

Cooling. Immediately after the buttermilk leaves the 
churn, the temperature should be reduced below 50 E. 
to prevent further development of acid and the separa- 
tion of the whey. Ordinary milk and cream coolers with 
enlarged holes in the distributing receptacle will answer 
very satisfactorily. 

Straining. As soon as cooled, the buttermilk should 

98 



SKIMMILK-BUTTBRMILK 99 

be run through a strainer consisting of one thickness of 
cheese cloth to remove any unbroken curd clots. 

Bottling. After it is strained the buttermilk is bottled 
or put in tin cans holding from one to five gallons, after 
which it is placed in the refrigerator where it is held until 
ready for delivery. 

Marketing Skim=milk Buttermilk. In trying to sell 
skimmilk-buttermilk it is necessary in the first place, to ex- 
plain that this product, when made as herein described, is 
almost identical with the highest grade of natural butter- 
milk, both in composition and physical properties, and, 
therefore, in palatability and wholesomeness. Indeed, it 
is not thought possible under average conditions to secure 
natural buttermilk of as uniform a quality or as fine a 
flavor as can be obtained from skim-milk. When these 
facts are explained to dealers and consumers, any preju- 
dices which might exist against this so-called artificial 
product are certain to vanish. 

The dealers in buttermilk should be furnished with 
attractive signs, calling attention to the fact that the 
product is for sale by them. Buttermilk is not found at 
all soda fountains, and unless conspicuous signs are 
posted at these places, the public may not call for it. 

Buttermilk may readily be sold to drug stores, restau- 
rants, hotels and boarding houses at from ten to thirty 
cents per gallon, averaging about twelve cents per gallon. 

As with cottage cheese, the most satisfactory way of 
disposing of buttermilk is to sell it direct to the milk 
and cream customers along the dairy route. 

Where buttermilk is intended to be used as a beverage, 
it is important to keep its temperature below 50 F. until 
it is -consumed. 

Food Value of Buttermilk. When used as a bever- 



100 MARKET DAIRYING 

age, buttermilk is usually appreciated only for its palata- 
bility. Aside from this, however, it has a high dietetic, 
as well as high medicinal, value. In certain diseases, 
especially those affecting the alimentary tract, buttermilk 
is considered indispensable. Its nutritive value is high, 
two quarts being approximately equal to one pound of 
good beefsteak. 

Buttermilk From Pasteurized Skim=milk. The best 
buttermilk is obtained by adding the starter to pasteurized 
skim-milk. Under such conditions the entire skim-milk 
becomes virtually a starter or pure culture of lactic acid 
bacteria. This not only means a better flavor but also 
insures freedom from pathogenic organisms. Pasteuriza- 
tion also lessens the tendency for the whey to separate. 



CHAPTER XV. 



MAKING AND MARKETING ICE CREAM. 



hot 

As 



For the best quality of ice cream use cream containing 
about 20 % butterfat. Put the cream into a tin 
can and pasteurize it as follows : Place the can in 
water and stir slowly, but constantly, while heating, 
soon as the temperature reaches 
150 F. remove the cream from 
the hot water and let it stand 
at room temperature from ten 
to fifteen minutes, then cool 
quickly to near the freezing tem- 
perature. 

Pasteurization improves the 
quality of the ice cream, giving 
it a much smoother body, and 
also destroys practically all of 
the bacteria. 

Vanilla Flavor. Vanilla is 
the most popular of ice cream 
flavors. The best vanilla flavor 
is obtained by using the best 
Mexican vanilla bean. Not only 
does this bean give the best 
flavor, but it costs less than half Fig ' 44 - Vanilla Beans - 
as much as the vanilla extracts. The best beans are very 
oily and pliable, about nine inches long, very fragrant 
and closed, leaving none of the seeds exposed. 

The flavor is prepared by cutting the beans in small 
101 




102 MARKET DAIRYING 

pieces and grinding them with loaf sugar. Immediately 
after grinding, the vanilla sugar is bottled and corked 
and set aside until ready for use. On an average one and 
one-half beans are required per gallon of cream. 

Vanilla Ice Cream. In pasteurizing, as soon as the 
temperature reaches 150 F. add sugar at the rate of one 
and three-fourths pounds per gallon of cream. This 
amount includes the vanilla sugar. Next add the vanilla 
sugar, thoroughly mix, and just before cooling, strain 
through one thickness of cheese cloth if the seeds are to 
be retained in the cream, and through four thicknesses if 
they are to be excluded. The sugar will dissolve much 
more quickly and the flavor will be more thoroughly ab- 
stracted from the ground beans when both are added 
while the cream is still hot. Hot cream also strains far 
more quickly than cold. 

Freezing. Crush ice to moderate fineness in a strong 
wooden box with a heavy round stick shaped like a potato 
masher. Pack this around the freezing can, using three 
parts of ice to one of ice cream salt. Start the freezer 
as soon as the cream begins to freeze to avoid crystals. 
There is danger of churning the cream when the freezer 
is started while the cream is still warm. As soon as it 
becomes difficult to turn the freezer longer, remove the 
beater, scrape all cream from it and pack the cream closely 
in the can. The cream may now be packed at once into 
small retail packing cans, or the brine may be removed, 
more crushed ice and salt added, and the cream kept in 
the freezer until needed for packing for retail trade. 

Lemon Ice Cream. In making lemon flavored ice 
cream use the best paper-wrapped lemons, free from any 
signs of decay. Wash the lemons lightly in cold water 
and grate of! the outer, yellowish portion of the rind, 



ICE CREAM 103 

being careful not to grate off any of the white por- 
tion which is very bitter. Mix the grated rind with 
sugar, using one ounce of sugar for each lemon rind. 
Next cut the lemons in two and squeeze out the juice, re- 
moving any seeds that may have dropped in from the 
squeezer. Mix the juice with the sugared rind and add 
orange juice to the mixture, using one orange to every 
five lemons. Allow the mixture to stand for about one 
hour, stirring it occasionally, and then strain. Use at 
the rate of one and one-half gills (4 gills = 1 pint) per 
gallon of cream. The flavor may be beaten into the cream 
after it is frozen, or it may be added when the cream is 
partially frozen. The latter is the more convenient 
method, since the paddles in the freezer will accomplish 
the mixing. 

In making lemon ice cream, use at the rate of two 
pounds of sugar per gallon of cream, instead of one and 
three-fourths as for vanilla ice cream. In other respects 
the cream is treated and handled the same as in making 
vanilla ice cream. 

Packing Ice Cream. Cream that is to be retailed 
within a day after freezing should be packed into one- 
quart, two-quart, one-gallon, or larger, packing cans im- 
mediately after freezing. The packing cans should be 
clean, sterile, and cool when the cream is packed into 
them. Fill them by means of a large spoon or dipper, 
thoroughly packing the cream so as to leave no air spaces. 
Put the cover on securely and thoroughly coat the edge 
with butter to keep out brine. This done, place the 
packed can of cream in the proper sized tub and pack with 
ice and salt the same as for freezing, using however 
most of the salt near the top. It is also better to have 
the ice somewhat coarser for packing than for freezing. 



104 



MARKBT DAIRYING 



To eliminate all danger of brine entering the can, it is 
necessary to have a hole in the tub at a point, say, one 
inch below the top of the can within it. 

If sonic of the cream is to be held longer than a day 
after freezing, it is better to leave it packed in the freezer 
until called for by the consumer. Cream can be kept 
frozen in bulk more conveniently than in small packing- 
cans, and will require also less ice and salt. Where ice 
cream is kept in bulk as here indicated, it should not be 




Pig. 45.— Packing Can. 




Fig. 46.— Packing Tub. 



kept frozen too hard, else there will be difficulty in getting 
it packed solidly into the small cans. 

Ice cream must not be allowed to melt in the packing 
cans. Remove the brine and repack with ice and salt 
often enough to prevent melting. In the melting process 
the water separates and this forms undesirable crystals 
when the cream is refrozen. 



tCB CRBAM 105 

Overrun. 'This refers to the excess of ice cream over 
cream. Anything that lends to incorporate and hold air 
in cream conduces to a large overrun. Thus excessive 
heating of the cream during freezing mixes a great deal 
of air with it, and hence increases the overrun. A high 
viscosity of the cream holds the air incorporated during 
freezing. Fresh separator cream has a low viscosity, that 
is, does not whip well, hence will not swell up so much 
in freezing as cream that has been kept cold for twenty- 
four hours. Pasteurized cream also has a low viscosity, 
but this will improve by keeping the cream at a low tem- 
perature a number of hours before freezing. 

With pasteurized cream and a speed of about eighty 
revolutions per minute, there will be an overrun of from 
twenty-five to thirty-three per cent. With unpasteurized 
cream and a high speed of the freezer, the overrun may be 
increased to fifty per cent. 

Large overruns are always obtained at the expense of 
quality. 

Marketing Ice Cream. Hardly any attempt has yet 
been made by cream producers living within driving dis- 
tance of cities to convert their cream into ice cream 
and sell this product direct to consumers. This is some- 
what surprising, since the largest profits in the cream 
business have hitherto been made by what may be called 
the middleman, the city ice cream manufacturer. 

It is a vital matter with producers to reach consumers 
direct wherever this is possible, and thus save the mid- 
dleman's profits. With those who retail milk and cream, 
the marketing of ice cream would entail no extra expense. 

The essential thing in building up a good ice cream 
trade is to make the best product possible. The market 
is glutted with cheap, inferior ice cream, and the call 



106 MARKET DAIRYING 

now is for a high grade product. Fortunately the public 
is beginning to realize that there is positive danger in 
eating ice cream made from old, stale milk or cream, and 
the public also seems to begin to understand that the 
bulk of ice cream is made with so-called thickeners, like 
gelatine, corn starch, tapioca, arrow root, and others. 
Many so-called ice creams contain no cream whatever. 
The highest quality of ice cream contains nothing but 
good, pure cream, sugar and flavoring. 



CHAPTER XVI. 

RELATIVE MARKET VALUE OF MILK AND ITS PRODUCTS. 

Many milk producers are so situated as to make it pos- 
sible for them to sell either milk, cream, butter, cheese 
or ice cream. To those so situated the question naturally 
arises, what method of disposal will yield the largest re- 
turns? This, of course, will depend to a great extent 
upon the relative market prices of these products. 

To show how dairymen may determine for themselves 
in what form they can realize most for their milk, a 
simple method of calculation is here presented, in which, 
for purposes of illustration, the following prices have 
been adopted: Milk, seven cents per quart; 30% cream, 
one dollar per gallon ; butter, twenty-five cents per pound ; 
cheese, ten cents per pound; and ice cream, made from 
15% cream, one dollar per gallon. Using these as average 
prices for a given locality, determine the relative re- 
turns from one hundred pounds of milk containing 4% 
(4 lbs.) butterfat, (1) when retailed as milk, (2) when 
sold as cream, (3) when sold as butter, (4) when sold 
as cheese, and (5) when sold as ice cream. 

1. Value of Milk. Since milk weighs 2.15 pounds per 
quart, 100 pounds of 4% milk are equal to 46.5 quarts, 
which, at 7 cents per quart, are worth $3.25. 

2. Value of Cream. One hundred pounds of 4% milk 
will make 13.33 pounds of 30% cream, as determined by 
the following rule: 

107 



108 MARKET DAIRYING 

Rule: To find the number of pounds of cream that 
can be obtained from a given amount of milk, multiply 
the milk by its test and divide the product by the test 
of the cream. Thus the amount of 30% cream from 
100 pounds of milk testing 4% equals 

100 X 4 

— — — = 13-33 pounds. 

Since a gallon of 30% cream weighs practically the 
same as a gallon of water (8.35 lbs.), the 13.33 pounds 
of cream are equal to 1.6 gallons which, at $1.00 per gal- 
lon, are worth $1.60. Allowing one-half cent per pound 
for skim-milk, we have 43 cents as the value of the 86 
pounds of skim-milk, which gives a total value of $2.03 
for the 100 pounds of 4% milk. 

2. Value of Butter. One hundred pounds of 4% milk 
will yield 4 2-3 pounds of butter, because where up-to- 
date methods of creaming and churning are followed 
every pound of butterfat will make 1 1-6 pounds of 
butter. Four and two-thirds pounds of butter at 25 cents 
per pound are worth $1.17. Valuing buttermilk at the 
same price as skim-milk (one-half cent per pound) 48 
cents should be added to the $1.17 as the value of the 
skim-milk and buttermilk, making a total value of $1.65 
for the 100 pounds of 4% milk. 

4. Value of Cheese. Since one pound of butterfat yields 
approximately 2.6 pounds of cured cheddar cheese, 100 
pounds of 4% milk will make 4 X 2.6, or 10.4 pounds of 
cheese, which, at 10 cents per pound, are worth $1.04. 
Allowing 10 cents as the value of the whey from the 100 
pounds of 4% milk, we get a total value of $1.14. 



VALUE OF MILK AND ITS PRODUCTS 109 

5. Value of Ice Cream. Since a gallon of 15% cream 
weighs 8.45 pounds, 100 pounds of 4% milk will make 
3.15 gallons of 15% cream (see formula for calculating 
cream, p. 108) or, allowing an overrun of 33 1-3%, 4.2 
gallons of ice cream. At $1.00 per gallon this is worth 
$4.20. To this must be added the value of J$ pounds of 
skim-milk which, at one-half cent per pound, are worth 
$j cents, making a total value of $4.57 for the 100 pounds 
of milk made into ice cream. 

Summary. The preceding calculations show that 100 
pounds of 4% milk are worth 

$1.14 when sold as cheese, 
1.65 when sold as butter, 
2.03 when sold as cream, 
3.25 when retailed as milk, 
4.57 when sold as ice cream. 

It is to be remembered that the above figures show the 
relative gross returns at the prices given. The net re- 
turns will vary greatly, depending largely upon the near- 
ness to market and the quantity of milk handled ; also to 
some extent upon the use to which the skim-milk is put. 
If fed to pigs and calves the value of skim-milk is less 
than one-half cent per pound; if made into buttermilk or 
cottage cheese its value may range from one to two 
cents per pound. 

Table of Values. The following table of values has 
been prepared for handy reference. The price of milk is 
used as a basis, and the table shows at what prices cream 
and butter must be sold to give the same returns as milk : 



110 



MARKET DAIRYING 



Per Cent, of 
Fat in Milk 


When Milk 
sells at 


20 % Cream 
must sell at 


30 % Cream 
must sell at 


Butter 
must sell at 


3.5 


5c per quart 
6c " 
8c " 
10c " 


25c per quart 
31c " 
42c " 
53c " 


36c per quart 
43c " 
59c " 
75c " 


50c per pound 
60c " 
84c " 

$1.06 " 


4.0 


5c per quart 
6c " 
8c " 
10c " 


22c per quart 
27c " 
37c " 
46c " 


31c per quart 
38c " 
50c " 
66c " 


44c per pound 
54c " 
73c " 
93c " 


4.5 


5c per quart 
6c " 
8c " 
10c " 


20c per quart 
24c " 
32c " 
41c " 


28c per quart 
34c " 
46c " 
59c " 


39c per pound 
47c " 
65c " 

82c " 


5.0 


5c per quart 
6c " 
8c " 
10c " 


18c per quart 
21c " 
29c " 
37c " 


25c per quart 
30c " 
42c " 
53c " 


35c per pound 

43c " 

59c " 

75c " " 



In calculating the above values, skim-milk and butter- 
milk have been rated at 30 cents per 100 pounds. The 
weight allowed per quart is as follows : Milk, 2.15 pounds ; 
20% cream, 2.1 pounds; and 30% cream, 2.0 pounds. 
The cost of handling and retailing these products, as well 
as the cost of making the butter, has not been considered. 

From the table it will be seen that when 3.5% milk sells 
at 5 cents per quart, 20% cream must sell at 25 cents per 
quart, 30% cream at 36 cents per quart, and butter at 50 
cents per pound, to yield equivalent returns. Similarly, 
when 5% milk sells at 5 cents per quart, 20% cream must 
sell at 18 cents per quart, 30% cream at 25 cents per 
quart, and butter at 35 cents per pound. 

The table emphasizes the importance of selling milk on 
the basis of its fat content. 



CHAPTER XVII. 

FARM BUTTERMAKING. 

Cream Ripening. Cream ripening is a process of fer- 
mentation in which the lactic acid organisms play the 
chief role. In every-day language, cream ripening means 
the souring of the cream. So important is this process 
that the success or failure of the butter maker is largely 
determined by his ability to exercise the proper control 
over it. In common practice the time consumed in the 
ripening of cream varies from twelve to twenty-four 
hours! 

Since the lactic acid bacteria play such an important 
part in the production of fine butter, it is obvious that 
the best results are obtained by ripening the cream with 
a starter or pure culture of lactic acid bacteria (see 
page 90). The more starter used in ripening the cream 
the better the results, provided the ripening is kept under 
good control. 

The sooner the cream is ripened after it leaves the 
separator the better the quality of the butter. If cream 
is to be churned every other day, it is best to ripen the 
first day's cream at once and then hold it at a low tem- 
perature until the second day's cream is to be ripened. 

Where attempts are made to hold cream sweet several 
days before ripening it, the undesirable bacteria usually 
get the upper hand of the lactic acid organisms and the 
result is the production of undesirable flavors. 

Objects of Ripening Cream. The ripening of cream 
has for its prime object the development of flavor and 

111 



112 MARKET DAIRYING 

aroma in butter, two qualities usually expressed by the 
word flavor. In addition to this, cream ripening has 
several minor purposes, namely : ( I ) renders cream more 
easily churnable ; (2) obviates difficulties from frothing 
or foaming in churning; (3) permits a higher churning 
temperature; (4) increases the keeping quality of butter. 

Flavor. This, so far as known at the present time, 
is the result of the development of the lactic fermentation. 
If other fermentations aid in the production of this im- 
portant quality of butter, they must be looked upon as 
secondary. In practice the degree or intensity of flavor 
is easily controlled by governing the formation of lactic 
acid. That is, the flavor develops gradually with the in- 
crease in the acidity of the cream. Sweet cream butter, 
for example, is almost entirely devoid of flavor, while 
cream with an average richness possesses the maximum 
amount of good flavor possible when the acidity has 
reached .6%. 

Churnability. Practical experience shows that sour 
cream is more easily churnable than sweet cream. This 
is explained by the fact that the development of acid in 
cream tends to diminish its viscosity. The concussion pro- 
duced in churning causes the little microscopic fat glob- 
ules to flow together and coalesce, ultimately forming the 
small granules of butter visible in the churn. A high 
viscosity impedes the movement of these globules. It is 
evident, therefore, that anything that reduces the viscosity 
of cream, will facilitate the churning. 

As a rule, too, the greater the churnability of cream the 
smaller the loss of fat in the buttermilk. 

Frothing. Experience shows that ripened cream is 
less subject to frothing or foaming than unripened. This 
is probably due to the reduced viscosity of ripened cream 
and the consequent greater churnability of same. 



FARM BUTTBRMAKING 113 

Temperature. Sour cream can be churned at higher 
temperatures than sweet cream with less loss of fat in 
the buttermilk. This is of great practical importance 
since it is difficult to get low enough temperatures for the 
successful churning of sweet cream. 

Keeping Quality. It has been found that butter with 
the best keeping quality is obtained from well ripened 
cream. It is true, however, that butter made from cream 
that has been ripened a little too far will possess very 
poor keeping quality. An acidity of .5% should be placed 
as the limit when good keeping quality is desired. 

control of the; ripening process. 

We have learned that the highly desirable flavor and 
aroma of butter are produced by the development of the 
lactic fermentation. In the following discussion we shall 
take up the means of controlling this fermentation and 
treat of the more mechanical side of cream ripening. This 
will include: (1) the ripening temperature; (2) time 
in ripening; (3) agitation of cream during ripening. 

Ripening Temperature. Since the lactic acid bac- 
teria develop best at a temperature of 90 to 98 F. 
it would seem desirable to ripen cream at these tem- 
peratures. But this is not practicable because of the 
unfavorable effect of high temperatures on the body 
of the cream and the butter. Good butter can be pro- 
duced, however, under a wide range of ripening tem- 
peratures. The limits may be placed at 6o° and 8o°. 
Temperatures below 6o° are too unfavorable for the 
development of the lactic acid bacteria. Any check 
upon the growth of these germs increases the chances 
for the development of other kinds of bacteria. But 
it may be added that when cream has reached an 



114 MARKET DAIRYING 

acidity of .4% or more, the ripening may be finished at a 
temperature between 55 and 6o° with good results. In 
general practice a temperature between 6o° and 70 ° gives 
the best results. This means that the main portion of the 
ripening is done at this temperature. The ripening is 
always finished at temperatures lower than this. 

Time in Ripening. As a rule quick ripening gives 
better results than slow. The reason for this is evident. 
Quick ripening means a rapid development of the lactic 
fermentation and, therefore, a relatively slow develop- 
ment of other fermentations. Practical experience shows 
us that the growth of the undesirable germs is slow in 
proportion as that of the lactic is rapid. For instance, 
when we attempt to ripen cream at 55 ° F., a tempera- 
ture unfavorable for the growth of the lactic acid bac- 
teria, a more or less bitter flavor is always the result. 
This is so because the bitter germs develop better at low 
temperatures than the lactic acid bacteria. 

Stirring Cream. It is very essential in cream ripen- 
ing to agitate the cream frequently to insure uniform 
ripening. When cream remains undisturbed for some 
time the fat rises in the same way that it does in milk, 
though in a less marked degree. The result is that the 
upper layers are richer than the lower and will sour less 
rapidly, since the action of the lactic acid germs is 
greater in thin than in rich cream. 

Thjs uneven ripening leads to a poor bodied cream. 
Instead of being smooth and glossy, it will appear coarse 
and curdy when poured from a dipper. The importance 
of stirring frequently during ripening should therefore 
not be underestimated. 

The Use of Sour Milk (Starter). Cream produced 
under cleanly conditions ordinarily contains many kinds 



FARM BUTTBRMAKING 115 

of bacteria — good, bad, and indifferent — and to insure a 
large predominance of the lactic acid type in the ripening 
process, it is necessary to reinforce the bacteria of this 
type already existing in the cream by adding large quan- 
tities of them in a pure form, that is, unmixed with un- 
desirable species. Clean flavored sour milk or skim milk 
at the point of curdling is practically a pure culture of 
lactic acid organisms, and the addition of about 10 pounds 
of such milk to every ioo pounds of cream will result 
in a better and more uniform quality of butter. 

Amount of Acid to Develop. Cream of average rich- 
ness should have an acidity of from 0.5 to 0.6 per cent, 
when churned. A rich cream requires less acid than a 
thin cream. 

Sweet and Sour Cream. In small dairies, where only 
a few churnings are made weekly, care should be taken 
never to mix sweet and sour cream just before churning. 
This always results in a heavy loss of fat in the butter- 
milk on account of the difference in the churnability of 
sweet and sour cream. 

ACID TEST FOR CREAM. 

Butter makers do not find it safe to rely upon their 
noses in determining the ripeness of cream for churning. 
They use in daily practice tests by which it is possible to 
determine the actual amount of acid present. The method 
of using these tests is based upon the simplest form of 
titration, which consists in neutralizing an acid with an 
alkali in the presence of an indicator which determines 
when the point of neutrality has been reached. 

In the tests for acidity of cream the alkali used is 
sodium hydroxide. This is made up of a definite strength 



116 



MARKET DAIRYING 



so that the amount of acid can be calculated from the 
amount of alkali used. 

Farrington's Alkaline Tablet Test. In this test the 
alkali is used in a dry tablet form in which it is easily 
handled. Each tablet contains enough alkali to neutralize 
.034 gram of lactic acid. 

Apparatus Used for the Test. This is shown in Fig. 
47 and consists of a porcelain cup, one 17.6 c.c. pipette, 
and a 100 c.c. rubber-stoppered, graduated glass cylinder. 




CYUNDEJii. 



Fig. 47. Farrington Acid Test Apparatus. 



Making the Solution. The solution is made in the 

graduated cylinder by dissolving 5 tablets in enough water 
to make 97 c.c. solution. When the tablets are dissolved, 
which takes from six to twelve hours, the solution should 
be well shaken and is then ready for use. The solution 
of the tablets may be hastened by placing the graduate in 
a reclining position, as shown in the cut. 



FARM BUTTBRMAKING 117 

Making the Test. With the pipette add 17.6 c.c. of 
cream to the cup, then with the same pipette add an equal 
amount of water. Now slowly add of the tablet solution, 
rotating' the cup after each addition. As soon as a per- 
manent pink color appears, the graduate is read and the 
number of c.c. solution used will indicate the number of 
hundredths of one per cent of acid in the cream. Thus, 
if it required 50 c.c. of the tablet solution to neutralize the 
cream then the amount of acid would be .50%. From 
this it will be seen that with the Farrington test no calcu- 
lation of any kind is necessary. 

CHURNING. 

Under the physical properties of butter fat it was 
mentioned that this fat existed in milk in the form of 
extremely minute globules, numbering about 100,000,- 
000 per drop of milk. In rich cream this number is in- 
creased at least a dozen times owing to the concentration 
of the fat globules during the separation of the milk. 

So long as milk and cream remain undisturbed, the fat 
remains in this finely divided state without any tendency 
whatever to flow together. This tendency of the globules 
to remain separate was formerly ascribed to the supposed 
presence of a membrane around each globule. Later re- 
searches, however, have proven the falsity of this theory 
and we know now that this condition of the fat is due 
to the surface tension of the globules and to the dense 
layer of casein that surrounds them. 

Any disturbance great enough to cause the globules to 
brsak through this caseous layer and overcome their sur- 
face tension will cause them to unite or coalesce, a process 
which we call churning. In the churning of cream this 



118 MARKET DAIRYING 

process of coalescing continues until the fat globules have 
united into masses visible in the churn as butter granules. 

CONDITIONS THAT INFLUENCE; CHURNING. 

There are a number of conditions that have an impor- 
tant bearing upon the process of churning. These may 
be enumerated as follows : 

i. Temperature. 

2. Character of butter fat 

3. Acidity of cream. 

4. Richness of cream. 

5. Amount of cream in churn. 

6. Speed of churn. 

7. Abnormal fermentations. 

1. Temperature. To have the miscroscopic globules 
unite in churning they must have a certain degree of soft- 
ness or fluidity, which is greater the higher the tempera- 
ture. Hence the higher the temperature, within certain 
limits, the quicker the churning. To secure the best re- 
sults the temperature must be such as to churn the cream 
in from thirty to forty-five minutes. This is brought 
about in different creams at quite different temperatures. 

The temperature at which cream must be churned is 
determined primarily by the character of the butter fat 
and partly also by the acidity and richness of the cream. 
Most cream is churned between 55 and 60 degrees Fahr. 

Rule for Churning Temperature. A good rule to fol- 
low with regard to temperature is this : When the cream 
enters the churn with a richness of 30 per cent and an 
acidity of .5 to .6 per cent, the temperature should be 
such that the cream will churn in from thirty to forty- 
five minutes. This will insure an exhaustive churning 
and leave the butter in a condition in which it can be 



FARM BUTTMRMAKING 119 

handled without injuring its texture. Moreover, the but- 
termilk can then be easily removed, so that when a plug 
is taken with a trier the day after it is churned the brine 
on it will be perfectly clear. 

2. Character of Butter Fat. The fat globules in 
cream from different sources and at different times have 
the proper fluidity to unite at quite different temperatures. 
This is so because of the differences in the relative amount 
of "soft" and "hard" fats of which butter fat is composed. 
When the hard fats largely predominate the butter fat 
will, of course, have a high melting point. Such fat may 
be quite hard at a temperature of 6o°, while a butter fat 
of a low melting point would be comparatively soft at 
this temperature. For a study of the conditions that 
influence the hardness of butter fat the reader is referred 
to the discussion of the "insoluble fats" treated in the 
chapter on milk. 

3. Acidity of Cream. This has a marked influence on 
the churning process. Sour or ripened cream churns with 
much greater ease than sweet cream because the acid 
renders it less viscous. The ease with which the fat 
globules travel in cream becomes greater the less the 
viscosity. Ripe cream will therefore always churn more 
quickly than sweet cream. Ripe cream also permits of a 
higher churning temperature than sweet, which is of great 
practical importance where it is difficult to secure low 
churning temperatures. 

4. Richness of Cream. It may naturally be inferred 
that the closer the fat globules are together the more 
quickly they will unite with the same amount of concus- 
sion. In rich cream the globules are very close together, 
which renders it more easily churnable than thin cream. 



120 



MARKET DAIRYING 



The former can therefore be churned in the same length 
of time at a lower temperature than the latter. 

The ideal richness is about 30%. A cream much richer 
than this will stick to the sides of the churn, which re- 
duces the amount of concussion. The addition of water 
to the churn will overcome this stickiness and cause the 
butter to come in a reasonable length of time. It is bet- 
ter, however, to avoid an excessive richness when a ex- 
haustive churning is to be expected. 

5. Amount of Cream in Churn. The best and quick- 
est churning is secured when the churn is 
one-third full. With more or less cream 
than this, the amount of concussion is re- 
duced and the length of time in churning 
correspondingly increased. 

6. Speed of Churn. The speed of the 
churn should be such as to produce the great- 
est possible agitation or concussion of the 
cream. Too high or too low a speed reduces 
the amount of concussion. The proper speed 
for each particular churn must be determined 
by experiment. 

7. Abnormal Fermentations. The slimy 
j j| .or ropy fermentation sometimes causes trouble 

in churning by rendering the cream exces- 
sively viscous. Cream from single herds may 
become so viscous as to render churning im- 
possible. 

Dairy Thermometer. One of the essen- 
tials in making good butter is a thermometer 
ifairy like that shown in Fig. 48. It is necessary to 

eter. watch the temperature of the cream dur- 

ing ripening, and to secure uniform and exhaustive 



FARM BUTTBRMAKING 



121 



churnings the temperature of the cream must always be 
definitely known before it enters the churn. 

CHURNING OPERATIONS. 

Churns. Of the numerous styles of churns upon the 
market there is none better than the barrel churn. For 
large dairymen, however, who have 50 or more cows, a 
combined churn and butter worker is recommended. Such 
churns, of course, require some form of power to run 
them, and no large dairy is expected to be without power. 

Preparing the Churn. 
Before adding the cream, 
the churn should be scalded 
with hot water and then 
thoroughly rinsed with 
cold water. This will 
"freshen" the churn and 
fill the pores of the wood 
with water so that the 
cream and butter will not 
stick. 

Straining Cream. All 
cream should be carefully 
strained into the churn. 
This removes the possibil- 
ity of white specks in but- 
ter which usually consist of curd or dried particles of 
cream. 

Adding the Color. The amount of color to be added 
depends upon the kind of cream, the season of the year 
and the market demands. 

Jersey or Guernsey cream requires much less color 
than Holstein because it contains more natural color. 




Fig. 49-— Barrel Churn. 



122 MARKET DAIRYING 

During the summer when the cows are feeding on 
pastures the amount of color needed may be less than 
half that required in the winter when the cows are feed- 
ing on dry feed. 

Different markets demand different shades of color. 
The butter must therefore be colored to suit the market 
to which it is shipped. 

In the winter time about one ounce of color is required 
per one hundred pounds of butter. During the summer 
less than one-half ounce is usually sufficient. 

In case the color is not added to the cream (through an 
oversight) it may be added to the butter at the time of 
working by thoroughly mixing it with the salt. When the 
colored salt has been evenly distributed through the butter 
the color will also be uniform throughout. 

Gas in Churn. During the first five minutes of churn- 
ing the vent of the churn should be opened occasionally 
to relieve the pressure developed inside. This pressure 
according to Babcock, "is chiefly due to the air within 
becoming saturated with moisture and not to gas set free 
from the cream." 

Size of Granules. Butter should be churned until the 
granules are about half the size of a pea. When larger 
than this it is more difficult to remove the buttermilk and 
distribute the salt. When smaller, some of the fine grains 
are liable to pass out with the buttermilk, and the per- 
centage of water in the butter is reduced. When the 
granules have reached the right size, cold water may be 
added to the churn to cause the butter to float better. Salt 
will answer the same purpose. The churn is now given 
two or three revolutions and the buttermilk drawn off. 

Washing Butter. One washing in which as much 
water is used as there was cream is usually sufficient. 



FARM BUTTBRMAKING 123 

When butter churns very soft two washings may be ad- 
vantageous. . Too much washing is dangerous, however, 
as it removes the delicate flavor of the butter. 

Too much emphasis cannot be laid upon the importance 
of using clean,, pure water for washing. Experiments 
have shown that impure water seriously affects the flavor 
of butter. When the water is not perfectly pure it should 
be filtered or pasteurized. 

Salting. It is needless to say that nothing but the best 
grades of salt should be used in butter. This means salt 
readily soluble in water and free from impurities. If there 
is much foreign matter in salt, it will leave a turbid ap- 
pearance and a slight sediment when dissolved in a tumb- 
ler of clear water. 

Object of Salting. Salt adds flavor to butter and ma- 
terially increases its keeping quality. Very high salting, 
however, has a tendency to detract from the fine, delicate 
aroma of butter while at the same time it tends to cover 
up slight defects in the flavor. As a rule a butter maker 
will find it to his advantage to be able to salt his butter 
rather high. 

Rate of Salt. The rate at which butter should be 
salted, other conditions the same, is dependent upon mar- 
ket demands. The butter maker must cater to the mar- 
kets with regard to the amount of salt to use as he does 
with regard to color. 

The rate of salt used does not necessarily determine 
the amount contained in butter. For instance it is per- 
fectly possible under certain conditions to get a higher 
percentage of salt in butter by salting at the rate of one 
ounce per pound than is possible under other conditions 
by salting at the rate of one and a half ounces. This 
means that under some conditions of salting more salt is 
lost than under others. 



124 MARKET DAIRYING 

The amount of salt retained in butter is dependent 
upon : 

1. Amount of drainage before salting. 

2. Fineness of butter granules. 

3. Amount of butter in churn. 

1. When the butter is salted before the wash water 
has had time to drain away, any extra amount of water 
remaining will wash out an extra amount of salt. It is 
good practice, however, to use a little extra salt and 
drain less before adding it as the salt will dissolve better 
under these conditions. 

2. Small butter granules require more salt than large 
ones. The reason for this may be stated as follows : The 
surface of every butter granule is covered with a thin 
film of water, and since the total surface of a pound of 
small granules is greater than that of a pound of larger 
ones, the amount of water retained on them is greater. 
Small granules have therefore the same effect as insuffi- 
cient drainage, namely, washing out more salt. 

3. Relatively less salt will stick to the churn in large 
churnings than in small, consequently less will be lost. 

Standard Rate. The average amount of salt used in 
butter is one ounce per pound. 

WORKING BUTTER. 

Object. The chief object in working butter is to evenly 
incorporate the salt. It also assists in expelling any sur- 
plus moisture. 

How to Work Butter. Where only a small amount 
of butter is made, the butter may be worked with a ladle 
in the churn. For larger amounts it is desirable, however, 
to have a separate worker like that shown in Fig. 50. 



FARM BUTTBRMAKING 



125 




Fig. 50.— Butter worker. 



Butter is worked enough when the salt has been evenly 
distributed. Just when this point has been reached can 
not always be told from the appearance of the butter 
immediately after working. But after four or six hours' 

standing the appear- 
ance of white streaks 
or mottles indicates 
that the butter has 
not been sufficiently 
worked. The rule to 
follow is to work the 
butter just enough to 
prevent the appearance 
of mottles. To avoid 
mottles it is best to 
work butter twice. The 
first time, it is worked 




Fig. -31 — Butter Printer. 



126 MARKET DAIRYING 

just enough to fairly incorporate the salt. It is then 
allowed to stand six or eight hours, after which white 
streaks are usually noticeable on cutting the butter with 
a string. The second working should cease as soon 'as 
these streaks or mottles have been removed. 

Difficult Churning. The causes of trouble in churn- 
ing may be enumerated as follows: (i) thin cream, (2) 
low temperature, (3) sweet cream, (4) high viscosity of 
cream, (5) churn too full, (6) too high or too low speed 
of churn, (7) colostrum milk, (8) advanced period of 
lactation, and (9) abnormally rich cream. 

Foaming. This is usually due to churning a thin 
cream at too low a temperature, or to a high viscosity of 
the cream. When caused by these conditions foaming 
can usually be overcome by adding warm water to the 
churn. Foaming may also be caused by having the churn 
too full, in which case the cream should be divided and 
two churnings made instead of one. 

Cleaning Churns. After the butter has been removed, 
the churn should be washed, first with moderately hot 
water, next with boiling hot water containing a little 
alkali, and finally with hot water. If the final rinsing is 
done with cold water the churn dries too slowly, which 
is apt to give it a musty smell. This daily washing should 
be supplemented occasionally with a washing with lime 
water. 

Nothing is equal to the cleansing action of well pre- 
pared lime water and its frequent use will prevent the 
peculiar churn odor that is bound to develop in churns 
not so treated. 

The outside of the churn should be thoroughly cleaned 
with moderately hot water containing a small amount of 
alkali. 



FARM BUTTBRMAKING 127 

Marketing Butter. For fancy trade, one-pound prints 
wrapped in parchment paper are the most popular. These 
prints are made with a small hand printer (Fig. 51) 
which should have the dairyman's monogram cut into 
it. The imprint of the monogram in the butter will serve 
as a guarantee of its genuineness. It is also desirable to 
have some neat lettering on the parchment wrapper, such, 
for example, as Fancy Dairy "Butter, Cold Spring Dairy 




Fig. 52,-Print Butter Box. 

Butter, Golden Jersey Butter, etc. Prints must be kept 
cold to preserve their attractive rectangular appearance. 

The best prices for butter are realized by selling it di- 
rect to the consumer. With dairymen who retail milk 
and cream, this method of marketing not only yields the 
best prices but is also the most convenient, because the 
butter can be disposed of at the same time as the milk 
and cream. 

A covered box like that shown in Fig. 52 is best 
adapted for carrying print butter to market. Ice may be 
packed in the box with the butter during warm weather. 



128 MARKET DAIRYING 

Composition of Butter. According to analysis re- 
ported by various experiment stations, American butter 
has the following average composition : 

Per cent. 

Water 13 

Fat 83 

Proteids I 

Salt 3 





Fig. 53.— Butter Ladles. 



Fig. 64.— Butter Carton for 
Wrapping One-pound 
Butter Prints. 



CHAPTER XVIII. 

THE DAIRY HOUSE. 

Location. In selecting a site for a dairy house, con- 
venience and sanitation should be given first considera- 
tion. A well drained spot, free from rubbish and bad 
odors, and within reasonable distance from the barn 
should be selected. An abundance of good, pure water 
must be available. 

Floor Plans Designed by the Author. Dairymen who 
sell milk and cream occasionally have a surplus of these 
products on their hands, which is usually made into butter. 
Floor plans for dairy houses must therefore provide for 
small buttermaking outfits in addition to all the necessary 
apparatus for the handling of milk and cream. 

The floor plan shown in Fig. 55 is designed to meet 
the needs of small dairymen. Figs. 56 and 57 illustrate 
plans which will answer the needs of dairymen having 
from twenty to fifty cows. The first two plans provide 
for natural refrigeration; the last provides for artificial 
refrigeration. There is no question that refrigerating 
machinery can be employed very advantageously in a great 
percentage of the larger dairies. 

Details of Construction. The foundation for the 
walls may be constructed of stone, brick or concrete. It 
should rest upon firm, solid ground below the frost line, 
and the top must be at least one foot above ground. 

In building the walls, place the studs two feet apart 
9 

129 



130 



MARKET DAIRYING 




Fig. 55.— Floor Plan of Dairy House Suitable for Ten to Twenty Cows. 

and tack building paper on both sides. Weather 
board the outside and finish the inside as follows : 
Board up preferably with tongued and grooved 
lumber, and cover the boards with two thicknesses of 



THE DAIRY HOUSE 



131 




Fig. 56.— Floor Plan of Dairy House Suitable for Twenty to Fifty Cows. 
(Natural Refrigeration.) 18'x24'. 

roofing paper. Next put on furring strips, one foot apart, 
and to these fasten wire lathing. If the lathing is pro- 
vided with one-inch steel ribs the furring strips are not 



132 



MARKET DAIRYING 




Fig. 57.— Floor Plan of Dairy House Suitable for Twenty to 
Fifty Cows. (Mechanical Refrigeration.) 18'x30\ 



THE DAIRY HOUSE 133 

needed. Next apply one and one-half inches of cement 
plaster consisting of one part cement, three parts clean, 
coarse sand, and one part slacked lime paste. Press the 
concrete partly through the wire lathing. Finish with one 
part cement and one part sand and trowel off as smoothly 
as possible. This construction provides one three-fourths 
inch and one four-inch dead air spaces. 

The appearance of a wall thus constructed is much im- 
proved by coating it with a cement filler which gives it a 
uniform grayish color. If this is followed by two coats 
of white enamel laboratory paint, the walls present a very 
sanitary appearance. 

The author has thoroughly tested this enamel paint 
and has found it very satisfactory. The walls of the milk 
room especially should be painted with the enamel to 
within two or three feet of the floor. 

Construct a four-inch concrete floor upon a well tamped 
foundation consisting of gravel, cobble stones and cinders. 
These materials afford good drainage and thus prevent the 
cold and dampness usually associated with concrete floors. 
In preparing the concrete for the floor use one part 
cement, two parts clean, coarse sand and four parts 
gravel or crushed stone. Finish with one part cement and 
two parts sand. 

All parts of the floor should slope toward the drain in 
the center. Round out the corners and edges of the floor 
with concrete to make them more easily cleanable. 

To provide insulation for the concrete floor of the re- 
frigerator, asbestos or other insulating material is used 
as shown in Fig. 23. The asbestos must be protected from 
moisture by covering both sides with waterproof paper. 

The ceiling should be about twelve feet high and built 
of the best ceiling lumber. Keep "the ceiling well painted. 



134 



MARKET DAIRYING 



Enough windows must be provided to afford ample 
light and to admit sunshine to all parts of the building. 

Provide ventilation in the milk and wash rooms by- 
running tight ventilating shafts from the ceiling through 
the top of the roof. 

Sewerage. Effective sewerage must be provided at 
the time the floor is laid. A bell trap (Fig. 58) should 
be placed in the center 
of each room and care- 
fully connected with the 
sewer. Conduct the sew- 
age far enough away to 
keep its odors a safe 
distance from the dairy 
house. See chapter 

XXVI. 

Method of Warming 
Dairy Houses. Dairy 
houses should be heated with steam, not with stoves. 
Either the exhaust steam from the engine or steam taken 
directly from the boiler may be used for this purpose. The 
heating pipes should be so arranged that either may be 
used when desired. 

A very satisfactory method of piping is to run one and 
one-half inch pipes from the boiler to within two feet of 
the floor, and close to the walls. The pipes should pass 
around each room and end in a steam trap which dis- 
charges the condensed steam into a hot well located near 
the injector, so that the hot water may readily be drawn 
into the boiler. The heating pipes must all slope towards 
this well. 

A reducing valve should be placed near the boiler so 
that any amount of pressure may be carried in the heat- 




Fig. 58.- Bell Trap. 



THE DAIRY HOUSE 135 

ing pipes. With a good valve of this kind a pressure 
as low as one pound may be carried when the boiler 
pressure varies from twenty to fifty pounds. 

Screening. Where proper sanitation is expected it is 
absolutely necessary to guard against flies, and this can 
easily be done by screening all doors and windows. Flies 
are a prolific source of milk contamination and must 
therefore be rigidly excluded from the dairy. 



CHAPTER XIX. 

MECHANICAL REFRIGERATION. 

In warm climates and in localities where ice is not 
obtainable or only so at a high cost, cold may be produced 
by artificial means known as mechanical refrigeration. 
This system of refrigeration is also finding its way into 
dairies that are able to procure ice at a moderate cost 
but which are seeking more satisfactory means of control- 
ling the temperature of their milk, cream and refrigerator.' 
Most of the mechanical refrigerating machines in use at 
the present time belong to the compression type. What- 
ever is said here, therefore, will pertain strictly to this 
class of machines. 

Fig. 59 shows a desirable method of piping and also 
illustrates the circulation of the ammonia. The milk and 
cream are cooled with cold brine which is circulated by 
means of a pump. No ice is needed. When an especially 
low temperature of the brine is desired, as in making ice 
cream, valves A (Fig. 59) are shut off and valves B 
opened, leaving all of the ammonia to circulate through 
the brine tank. 

Principle of Refrigeration. The principle employed 
in mechanical refrigeration is the production of cold by 
the evaporation of liquids which have a low boiling point, 
like liquid ammonia, liquid carbonic acid, ether, etc. 

When a liquid evaporates or changes into the gaseous 
state it absorbs a definite amount of heat called heat of 

136 



MECHANICAL REFRIGERATION 



137 



vaporization or "latent" heat. Thus to change water from 
212° F. to steam at 21 2° F. requires a considerable 
amount of heat which is apparently lost, hence the term 
latent (hidden) heat. 




Fig. 59.— Showing Circulation of Ammonia in Mechanical Refrigeration. 

Ether changes into its gas at a much lower temperature 
than water which is illustrated by its instant evaporation 
when poured upon the hand. The heat of the hand in this 
case is sufficient to cause vaporization and the sensation of 
cold indicates that a certain amount of heat has been 
abstracted from the hand in the process. 



138 MARKET DAIRYING 

Manifestly for refrigerating purposes a liquid must be 
used that can be evaporated at a very low temperature; 
for the cold in mechanical refrigeration is produced by 
the evaporation of the liquid in iron pipes, the heat for 
the purpose being absorbed from the room in which the 
pipes are laid. Anhydrous ammonia has thus far proven 
to be the best refrigerant for ordinary refrigeration. 

Anhydrous Ammonia (Refrigerant). This substance 
is a gas at ordinary temperatures but liquifies at 30 F. 
under one atmospheric pressure. In practical refrigera- 
tion the ammonia is liquified at rather high temperatures 
by subjecting it to pressure. The ammonia is alternately 
evaporated and liquified so that it may be used over and 
over again almost indefinitely. 

Circulation of Ammonia. The cycle of operations in 
mechanical refrigeration is as follows : The liquid am- 
monia starts on its course from a liquid receiver, and 
enters the refrigerating coils in which it evaporates, ab- 
sorbing a large amount of heat in the process. By means 
of a compression pump, operated by an engine, the am- 
monia vapors are forced in the condenser coils where the 
ammonia, under pressure, is again liquified by running 
cold water over the coils. From the condenser coils it 
enters the liquid receiver, thence again on its journey 
through the refrigerating coils. 

The intensity of refrigeration is regulated by an ex- 
pansion valve, which is placed between the liquid receiver 
and the refrigerating coils. This valve may be adjusted 
so as to admit the desired quantity of liquid ammonia to 
the coils. 

Systems of Refrigeration. There are two ways in 
which the cooling may be accomplished by mechanical 
refrigeration: (1) by evaporating the liquid ammonia 



MECHANICAL REFRIGERATION 139 

in a series of pipes placed in the room to be refrigerated ; 
and (2) by evaporating the liquid ammonia in a series of 
coils laid in a tank of brine and using the cold brine for 
cooling purposes. The former is known as the direct 
expansion system, the latter as the indirect expansion or 
brine system. 

Brine System. Brine should be exclusively used for 
cooling milk and cream and also largely for cooling the 
refrigerator. It is desirable, however, to have a few 
direct expansion coils in the refrigerator which may be 
used when extra cold is desired. The brine tank is 
located near the ceiling in the refrigerator where it will 
serve the same purpose as an overhead ice box. Refrig- 
erating pipes may also be laid in the milk room for the 
purpose of controlling its temperature during the warm 
summer months. 

The brine is kept circulating by means of a brine pump. 

Strength of Brine. The brine is usually made from 
common salt (sodium chloride). The stronger the brine 
the lower the temperature at which it will freeze. Its 
strength should be determined by the lowest temperature 
to be carried in the brine tank. The table by Siebel on 
the next page shows the freezing temperature as well as 
the specific heat of brine of different strengths. 

The fact that the specific heat grows less as the brine 
becomes stronger shows it to be wise not to have the 
solution stronger than necessary, because the less the 
specific heat the less heat a given amount of brine is able 
to take up. 



140 



MARKET DAIRYING 



Percentage of salt by weight. 


Pounds of 

salt per 

gallon of 

solution. 


Freezing 

point (F.). 


• Specific 
heat. 


1 


0.084 
0.169 
0.256 
0.344 
0.523 
0.708 
0.897 
1.092 
1.389 
1.928 
2.488 
2.610 


30.5 
29.3 
27.8 
26.6 
23.9 
21.2 
18.7 
16.0 
12.2 
6.1 
0.5 
-1.1 


.992 


2 


.984 


3 


.976 


4 


.968 


6 


.946 


8 


.919 


10 


.892 


12 , 


.874 


15 


.855 


20 


.829 


25 


.783 


26 


.771 







Refrigerating Capacity. To speak of a machine of 
one ton refrigerating capacity, means that it will pro- 
duce, in the course of twenty-four hours, the amount 
of cold that would be given off by one ton of ice at 32 F. 
melting into water at the same temperature. Its actual 
ice making capacity is about 50% less. 

Size of Compressor.- If the equivalent of five hun- 
dred pounds of ice is needed per day, then a half ton com- 
pressor will answer, provided it is run twenty-four 
hours a day. But since it will not likely be convenient 
to run the compressor more than six hours a day, a ma- 
chine four times this size will be necessary. The larger 
the compressor the shorter the time it needs to be run. 
A two-ton refrigerating machine will be large enough 
for a fifty-cow dairy. 

Power Required to Operate. The power required 
per ton of refrigeration is less the larger the machine. 
With a two-ton compressor, the power required is about 
two and one-half horsepower per ton of refrigerating 
capacity in twenty-four hours. 



MECHANICAL REFRIGERATION 141 

Refrigerating Pipes. The refrigerating pipes vary 
from one to two inches in diameter. With moderately 
good insulation it is estimated that by the direct expansion 
system one running foot of two-inch piping will keep a 
room of forty cubic feet content at a temperature of 32 ° 
F. With brine nearly twice this amount of piping would 
be necessary. 

For cooling the brine in the brine tank, about 140 
feet of 1 Y\ -inch pipes are required per ton of refrigera- 
ting capacity. 

Expense of Operating. When a refrigerating plant 
has once been installed and charged with the necessary 
ammonia, the principal expense connected with it will 
be the power required to operate the compressor. This 
power is supplied by the engine that is used for the regu- 
lar dairy work. The ammonia, being used over and over 
again, will add but a trifle to the running expenses. 
Nor can the water used for cooling the ammonia vapors 
add much to the cost of operating. It is true, however,. 
that the refrigerating plant will require some of the dairy- 
man's time and attention, but this is probably no more 
than would be consumed in the handling of ice in the 
dairy. 

Charging and Operating an Ammonia Plant, This 
subject is so ably discussed in The Engineer by H. H. 
Kelley that the author feels he can do no better than 
present the following extracts from that article. 

"When about to start an ice or refrigerating plant, the 
first thing necessary is to see that the system is charged 
with the proper amount of ammonia. Before the ammonia 
is put in, however, all air and moisture must be removed ; 
otherwise the efficiency of the system will be seriously 
interfered with. Special valves are usually provided for 



142 MARKET DAIRYING 

discharging the air, which is removed from the system 
by starting the compressor and pumping the air out, the 
operation of gas cylinder being just the reverse of that 
when it is working ammonia gas. it is practically impos- 
sible to get all the air out of the entire system by this 
means, so that some other course must be taken to remove 
any remaining air after the compressor has been started 
at regular work. This can be accomplished by admitting 
the ammonia a little at a time, permitting the air to escape 
through a purge valve, the air being thus expelled by dis- 
placement. The cylinder containing the anhydrous am- 
monia is connected to the charging valve by a suitable 
pipe, and the valve opened. The compressor is then kept 
running slowly with the suction and discharge valves wide 
open and the expansion valve closed. When one cylinder 
is emptied put another in its place, being careful to close 
the charging valve before attempting to remove the empty 
cylinder, opening it when the fresh cylinder is connected 
up. 

"From sixty to seventy-five per cent of the full charge 
is sufficient to start with so that the air may have an 
opportunity of escaping with as little loss of ammonia as 
possible. An additional quantity of ammonia may then be 
put in each day until the full charge has been introduced. 
When the ammonia cylinders have been emptied and a 
charge of, say, seventy-five per cent of the full amount 
has been introduced, the charging valve is closed and the 
expansion valve opened. The glass gauge on the am- 
monia receiver will indicate the depth of ammonia. The 
appearance of frost on the pipe leading to the coils and 
the cooling of the brine in the tank will indicate that 
enough ammonia has been introduced to start with. It is 
sometimes difficult to completely empty an ammonia cylin- 



MECHANICAL REFRIGERATION 143 

der without first applying heat. The process of cooling 
being the same when the ammonia expands from the cylin- 
der into the system as when leaving the expansion valve, 
a low temperature is produced and the cylinder and con- 
nections become covered with frost. When this occurs 
the cylinder must be slightly warmed in order to be able 
to get all the ammonia out of it. The ammonia cylinders, 
when filled, should never be subjected to rough handling 
and are preferably kept in a cool place free from any lia- 
bility to accident. The fact that ammonia is soluble in 
water should be well understood by persons charging 
a refrigerating system, or working about the plant. One 
part of water will absorb about 800 parts Qf ammonia gas 
and in case of accident to the ammonia piping or machine, 
water should be employed to absorb the escaping gas. 
Persons employed about a plant of this kind should be 
provided with some style of respirator, the simplest form 
of which is a wet cloth held over the mouth and nose. 
"After starting the compressor at the proper speed and 
adjusting the regulating valve note the temperature of 
the delivery "pipe, and if there is a tendency to heat 
open it wider, and vice versa. This valve should be care- 
fully regulated until the temperature of the delivery pipe 
is practically the same as the water discharged from the 
ammonia condenser. With too light a charge of am- 
monia the delivery pipe will become heated even when 
the regulating valve is wide open. As a general thing 
when the plant is working properly the temperature of 
the refrigerator is about 15 lower than the brine being 
used, the temperature of the water discharged from the 
ammonia condenser will be about 15 lower than that of 
the condenser, the pointers on the gauges will vibrate the 
same distance at each stroke of the compressor and the 



144 MARKET DAIRYING 

frost on the pipes entering and leaving the refrigerator 
will be about the same. By placing the ear close to the 
expansion valve the ammonia can be heard passing 
through it, the sound being uniform and continuous when 
everything is working properly. 

"When air is present the flow of ammonia will be more 
or less intermittent, which irregularity is generally notice- 
able through a change in the usual sound heard at the ex- 
pansion valve. The pressure in tne condenser will also be 
higher and the effect of the apparatus as a whole will 
be changed, and, of course, not so good. These changes 
will be quickly noticed by a person accustomed to the 
conditions obtaining when everything is in order and 
working properly. 

"The removal of air is accomplished in practically the 
same manner as when charging the system, permitting 
it to escape through the purging valve a little at a time 
so as not to lose any more gas than is absolutely necessary. 

"The presence of oil or water in the system is generally 
detected by shocks occurring in the compressor cylinder. 

"In nearly all plants the presence of oil in the system of 
piping is unavoidable. The oil used for lubricating pur- 
poses, especially at the piston rod stuffing boxes, works 
into the cylinders and is carried with the hot gas into the 
ammonia piping, where it never fails to cause trouble. 
The method of removing the air from the system has 
already been referred to, but the removal of oil is accom- 
plished by means of an oil separator. This is placed in 
the main pipe between the compressor and the condenser, 
and is of about the size of the ammonia receiver. ' Some- 
times another oil separator is placed in the return pipe 
close to the compressor which serves to eliminate any 
remaining oil in the warmer gas and to remove pieces of 



MECHANICAL REFRIGERATION 145 

scale and other foreign matter which, if permitted to enter 
the compressor cylinder, would tend to destroy it in a 
very short time. 

"The oil, which always gets into the system sooner or 
later and in greater or less quantity, depending upon the 
care exercised to avoid it, acts as an insulator and pre- 
vents the rapid transfer of heat from the ammonia to the 
pipe that ought to obtain, and also occupies considerable 
space that is required for the ammonia where the best re- 
sults are to be obtained." 



CHAPTER XX. 

KEEPING ACCOUNTS. 

Various methods are followed in keeping accounts with 
patrons, but nearly all of them involve the use of tickets, 
route book, and some form of ledger. The method here 
described is recommended because of its simplicity. 

Tickets. Most customers prefer to settle their milk 
and cream accounts daily. This they do by purchasing a 
quantity of tickets from the milkman and handing them 
out every time milk or cream is purchased. 

The tickets should be used but once. Where they are 
repeatedly used they become dirty and a real source of 
danger. Passing from one household to another they 
are likely to become contaminated with disease germs 
and thus become the means of disseminating disease. 

The coupon ticket presented on the next page is one of 
the most satisfactory in use at the present time. The 
portion of the ticket above the perforations is retained by 
the milkman. If the ticket is paid for at the time of pur- 
chase, this must be indicated on the stub retained by the 
dairyman as well as on the customer's ticket. 

Coupon tickets are also used for cream and buttermilk. 
Tickets for different products should have different 
colors. 

Tickets are not absolutely necessary ; indeed, many cus- 
tomers prefer to do without them. Where no tickets are 



146 



KEEPING ACCOUNTS 147 

k...M~. o,,.....J&Le.. * mj 

To TICKETS $1.00. MILK. (Sy./.(H3I 



MILK. 






To SPRING VALLEY DAIRY, Dr. 

J. L JONES. Prop.. Middleton, N. Y. 



.}:*Jt~!< 



To TICKETS $100. 

Received Payment 
Date _ . 
^ SPRING VALLEY OAIRY. o j _: SPRING VAIJLEY DAIRY. © 

l ONE Of. MILK 2 I ONE QT. MILK | 

o MIDDLETON. N. Y. * j o MIDDLETON. N. Y. * 

VAfiLEY DAIRY. 2 { ^ SPRING VALLEY DAIRY. 2 
ml? I 

Y. 
' DAIRY 

a. 



* -.ONE QT. MILK | J ONE QT. Ml 

o MID0LETf)N. NY. * » o MIDDLETDN. N. Y 



j SPRING VALLEY DAIRY. o f ^ SPRING VALL 

= ONE qJt. MILK 2 | ! ONE QT. MILK 2 

o MIDDLETON. N. Y. 5j o MIDDLETflN, N. Y. * 

^ ^SPRING VALLEY DAIRY. o f ,J SPRING VALLEY DAIRY. © 

= ONE Of. MILK 2 ! ONE of. MILK 2 

"LEtON.N. Y. * I © MIDDLETON, N. Y. * 

— j ,..T * -^£~.^^^.-«* 

SPRING VALLEY DAIRY. © f ^ SPRING VAljLEY DAIRY. © 

ONE QT. MILK 2 I ONE QT- MILK 2 



Coupon Ticket. 



MIDDLEfON. N. Y. ^ \ B MIDDLETON. N. Y. 



148 



MARKET DAIRYING 



used, an account is rendered at the end of the month 
similar to that rendered by the grocer. 

Route Book. It is evident that if customers were 
always supplied with tickets and regularly paid for each 
delivery of milk or cream, no further record would 
be necessary. But customers will run out of tickets oc- 
casionally as well as forget to regularly hand them out, 
hence it is necessary for drivers to carry with them a 
record or route book in which each transaction is recorded 
at the time it is made. A form suitable for this purpose 
is shown below. 



j6Lda*rvQ*><~-, & *f 


/X*i^<*™-~,&' $ 


i 

> 


o 

<* 
a 
a 


MILK 


CREAM 


B M 


BOTTLES. 


Q 

< 

< 


MILK. 


CREAM. 


B. M 


BOTTLES. 


i 

<7 


1 
p 


| 


P 


§ 

a 


| 

X 

o 


a 
3 

\ 

8 


l 

s 


i 

B 
a 


i 


I 


i 

5 


i 

s 
a 


1 


1 


| 

s 

B 

B 


i 






































t 






































» 


























































■' 



















Form of Route Book. 



The route book consists of loose leaves, upon which 
the names of customers are arranged alphabetically. The 
leaves are renewed each month, the old one being placed 
on file for future reference. The letters b. m. stand for 
buttermilk. 

Ledger. As a rule all accounts are settled monthly. 
The ledger form shown below serves satisfactorily as a 
permanent monthly record. 

On the debit side are recorded the sales and the total 
value of the tickets purchased. On the credit side are 



KEEPING ACCOUNTS 



149 



recorded all the receipts for the same period. The balance 
represents the difference between the debits and credits. 



Dr. 


^^ ^yyixfit 


Cr. 


DATE 

1906. 

i 


tri 
to 

< 
o 


TICKETS. 


03 


DATE 

1908 




TICKETS. 


n 


j 

s 


i 


H 


* 


M 
8 


B 


Jan 1-31 


too 


3o 


10 


/o 


« 


Jan 1-31 


Iq.00 ?& 


10 


1 1 


44 














Bal. Jan 3) 


%ox> 


£ 





X 


V 


Bal Feb. 1 


&0V 


S 


o 


.2 


^ 








Feb. 1-29 




■^>^ 




• <» 







Form of Ledger. 

Monthly Statement. At the end of each month a 

statement should be rendered to customers showing their 
indebtedness. A form like that herewith shown answers 
the purpose satisfactorily. 



SPRIXGDALE SANTTARY DAIRY, 

4. C. BOONE. Proprietor 



Mjl 



J±. 



j&/J*UZf 



REIDSVILXJi:, N. H., 



toSPRINGDALE SANITARY DAIRY, db. 

J C. BOONE. Proprietor 





^t^*^^ y^oA / 


\ * 


$0 




m 


&A/-J* 


lf ^rvt-<«4^4-, y*u£*: <p %■ 


\ 3 


20 






« 


II ^C^Z^l. <&^/-a-*^. 2^> 


! 3l 


3lo 






»• 


$• ty~**X<^ i~Z&^~tlCA; & s~ 




Jgg 


Z 


& 


It 


&y, e^uaJL 






6 


<X> 




Ko. y wxt^^A£Zc^^je^ tvtt&Aj ? 






2 


/& 















Monthly Statement. 



150 MARKET DAIRYING 

Order Book for Supplies. For convenience as well 
as for permanent record, all orders should be made in 
duplicate in a book specially made for the purpose. The 
leaves in the order book are alternately marked "original" 
and "duplicate," the duplicate being made at the same 
time as the original by using carbon paper between the 
two. A suitable form of order blank is shown below. 

Original Springdale Sanitary Dairy. 

J. C. Boone, Prop. 

Order No Reidville, N. H 190. . 

To 

Dear Sir: Please deliver by the following: 



Invoice and ship to 

Springdale Sanitary Dairy, 

J. C. Boone, Prop., Reidville, N. H. 



CHAPTER XXI. 

PASTEURIZATION OF MILK AND CREAM. 

The process known as pasteurization derives its name 
from the eminent French scientist Pasteur. It consists 
in heating and cooling milk and cream in a manner which 
will destroy the bulk of bacteria in them, but which will 
leave their chemical and physical properties unchanged 
as far as possible. 

Advantages of Pasteurization. The advantages to 
be derived from pasteurization vary with the conditions 
under which the milk is produced and the efficiency with 
which the work is conducted. If the milk comes from 
dairies where disease and uncleanliness prevail, pasteur- 
ization will prolong the keeping quality of the milk and 
also materially lessen the danger from disease germs. 
If, on the other hand, healthfulness and cleanliness re- 
ceive the exacting attention which prevails on certified 
dairy farms, nothing can be gained by subjecting milk 
to the pasteurizating process. 

Disadvantages of Pasteurization. The principal dis- 
advantages are as follows: (i) the cost of pasteurizing 
apparatus; (2) the cost of pasteurizing; (3) the tendency 
to promote uncleanliness on the part of the producer; (4) 
the tendency to reduce the cream line on the milk ; 
(5) lessening of the whipping property of the cream; 
and (6) the tendency to impart a "cooked" flavor to the 
milk and cream. 

Methods of Pasteurization. Two general methods 

151 



152 MARKET DAIRYING 

are now in vogue : ( I ) the discontinuous method by which 
every particle of milk and cream is heated from ten to 
thirty minutes according as the temperature is high or 
low; (2) the continuous method by which milk and cream 
are permitted to pass in a constant stream through the 
pasteurizer and are subjected on an average less than 
one minute to the pasteurizing temperature. 

In general the most efficient pasteurization is obtained 
with the discontinuous method. 

Pasteurizing Temperatures. Obviously where milk 
is heated only a minute or less, a higher temperature 
must be employed than where it is heated for a much 
longer period of time. With the continuous method 
the temperature varies from 160 to 180 F. With 
the discontinuous method the temperature varies 
from 140 to 1 55 F. Exposing milk or cream to 
a temperature of 145 ° F. for twenty minutes results 
in very satisfactory pasteurization. The temperature and 
time of exposure should always be such as to insure the 
destruction of the tubercle bacillus, which is one of the 
most resistant of the disease bacteria most commonly 
found in milk. 

Quick Cooling. In pasteurizing the heating must be 
quickly followed by thorough cooling. This is an ex- 
tremely important part of the pasteurizing process. It is 
desirable that the temperature be reduced at once to 45 ° 
F. or below. 

Viscogin. Thorough pasteurization reduces the vis- 
cosity or whipping property of cream. To restore the 
original viscosity a solution of sucrate of lime is added, 
which is known as viscogin. This solution is made by 
adding an excess of slaked lime to three parts of sugar 
dissolved in five parts of water. The mixture is al- 



PASTEURIZATION 153 

lowed to stand twenty-four hours, after which the clear 
liquid at the top is poured from the sediment and pre- 
served in a stoppered bottle. 

Add one part viscogin to about 150 parts of cream. 
Never add so much as to render the cream alkaline. 

While viscogin is entirely harmless, it is nevertheless 
an adulterant and cream treated with it must be so 
labeled. 

Inefficient Pasteurization.- Milk that has been un- 
derheated is more dangerous than that which has not 
been heated at all. The reason for this is that inadequate 
heat in pasteurizing may destroy the lactic acid bacteria 
(which are easily killed) and by so doing actually better 
the conditions for the growth of the more resistant and 
obnoxious kinds. Lactic acid organisms are antagonistic 
to other classes of bacteria and are therefore a real safe- 
guard to milk. This makes it plain that unless milk is 
pasteurized at a temperature which will destroy the 
pathogenic and non-acid bacteria as well as the acid bac- 
teria, it is far better not to heat it at all. 

Pasteurization should be condemned where its only ob- 
ject is to keep milk sweet. Its real object should be to 
destroy all actively growing bacteria and especially all 
disease-producing organisms such as the tubercle bacillus 
which is among the most resistant. 

Pasteurizing in the Home. If milk must be pas- 
teurized to render it safe, there is no better place to do 
this than in the home where it is to be consumed. The 
pasteurizing is very easily and satisfactorily accomplished 
by the use of a small double milk or rice boiler which 
can be procured for about one dollar from hardware deal- 
ers everywhere. It is essential to stir the milk while 
heating and to use a reliable thermometer. 



CHAPTER XXII. 



CERTIFIED MILK. 



Definition. Certified milk is milk produced under 
conditions imposed by medical milk commissions, which 
usually employ a veterinarian, a bacteriologist and a 
chemist to look after the production of the milk. It must 




Fig. 60.— Sanitary Dairy Barn. (Da. Div., U. S. Dept. of A.) 

be free from disease germs and preservatives, must have 
a known chemical composition, and must be so produced 
and handled as to insure a minimum numoer of bacteria. 

154 



CERTIFIED MILK 155 

If the producer has complied with all the requirements 
he is furnished a certificate by the commission, which 
permits him to use the "certified" label on his products. 

The term "certified milk" is registered in the United 
States patent office and its use is legally permitted only 
on milk approved by medical milk commissions. 

Uses. Certified milk is now largely used for infants 
and invalids. There is, however, also a rapidly increasing 




Fig. 61.— Truman Sanitary Milk Pail. (Storrs, Conn. Station.) 

use made of this milk by the better informed people who 
realize the unsanitary condition of average market milk. 
Certified milk is the means of saving the lives of thou- 
sands of infants and its increasing use offers splendid 
opportunities for dairymen who are in a position to 
meet the requirements laid aown by medical commissions. 
Production and Handling. The general conditions 
called for in the production of "certified" milk are essen- 
tially the same as those stated in the chapter on "sanitary 
milk production." 



156 MARKET DAIRYING 

The cows, milkers and premises are regularly inspected, 
and the milk is regularly subjected to chemical and bac- 
teriological tests. The number of bacteria permitted by 
different commissions varies from 10,000 to 30,000 per 
cubic centimeter of milk ; and the fat content ranges from 
about 3.5 to 4.5 per cent. 

The milk bottles are sealed preferably with metallic 
caps bearing the date of bottling and the name of the 
commission, (see page 188). Delivery should be made 
within twenty-four hours after the milk is drawn and its 
temperature during this time should not exceed 45 ° F. 

In the dairy house arrangements must be such as to 
reduce contamination to a minimum. A receiving can 
placed in an ante-roOm is used by the milkers to empty 
their pails, and from this the milk is conducted into the 
milk room. A sterilizer with doors at both ends is pre- 
ferably placed between the milk room and the wash room, 
so as to enable the milkers to get their pails without enter- 
ing the milk room and, at the same time, to allow the 
sterilized bottles to be removed without entering the wash 
room. 

Profits. Obviously it costs more to produce certified 
than average market milk, but the additional cost is less, 
as a rule, than the increased price realized. Certified 
dairies that have failed to make money have almost in- 
variably invested more money in buildings and equipment 
than was actually necessary. It has been shown that this 
class of milk may be successfully produced in quite ordi- 
nary buildings and with moderately cheap equipment. 
What is of greatest importance is extreme cleanliness, 
which is achieved mainly through intelligent care and 
management of every detail of the work from start to 
finish. 



CHAPTER XXIII. 

THE CARE OE MIEK IN THE HOME. 

No matter how good the condition of the milk when 
delivered, if carelessly handled in the home it will keep 
sweet but a very short time and the dairyman will get 
the blame. It is of vital interest to dairymen, therefore, 
to instruct their customers in the proper care of the milk 
in the home. 

There is no doubt that a great deal of good milk 
is spoiled in the home of the consumer. This, as a 
rule, is the result of ignorance. Few consumers have a 
good knowledge of milk and, therefore, do not know how 
to care for it. If milk producers will bring the following 
suggestions to the attention of their customers, it may 
relieve them of much of the complaint they have hitherto 
been obliged to suffer : 

INSTRUCTIONS TO CONSUMERS. 

To keep milk and cream sweet and pure, they must be 
kept cold and clean. As soon as the milk is delivered, it 
should be put in a cool place — a clean refrigerator if 
possible. The vessels in which the milk and cream are 
kept must be sterile and covered. Vessels are not sterile 
unless they have been kept in boiling water for five 
minutes and then inverted upon a clean shelf without 
wiping. 

157 



158 * MARKET DAIRYING 

On account of their great absorption properties milk 
and cream must be kept in covered vessels, especially when 
placed in the kitchen or cellar or possibly in the refrigera- 
tor with fruits and vegetables. Aside from absorbing 
odors when exposed in these places, they will also take 
up bacteria which will shorten their keeping quality. 

At 45 F. milk may be kept perfectly sweet for twenty- 
four hours, while at a temperature of 70 ° it may sour in 
less than six hours. This emphasizes the importance of 
cold in preserving milk and cream. 

Pour milk from one vessel to another as little as pos- 
sible to avoid contamination. The best plan is to keep 
it in the original bottles. 

Do not add new milk to old milk; neither add warm 
milk to cold. 

The tops of the bottles should always be washed before 
removing any milk. They are more or less contaminated 
with dust during transportation and also become soiled 
from the hands. 

Always clean the bottles before returning them. 

Finally it is well to remember that the lowest-priced 
milk is usually also the poorest and dirtiest. Such milk 
in the end will prove the most expensive. 



CHAPTER XXIV. 

THE BOILER AND ITS MANAGEMENT. 

A boiler is indispensible in a well equipped dairy. The 
steam which it provides is important, not only in securing 
hot water and in sterilizing, but also in furnishing power. 
A steam engine will be found useful in most dairies for 
pumping water, separating milk, churning and freezing 
cream, and by extending the shaft through one side of 
the building its usefulness may be extended to sawing 
wood, washing clothes, running, the grindstone, etc. 

For the smaller dairies the upright form of boiler will 
be found the most satisfactory. But for dairies having 
upwards of fifty cows, the horizontal form of fire-tube 
boiler should be used. The latter style is laid in- brick. 
The grates are supported upon brickwork and heat and 
smoke pass along the underside of the boiler toward 
the rear and return through the fire-tubes. To prevent 
radiation of heat the brick work must be built up to 
cover the entire boiler. The fire box must be constructed 
of the best fire brick. 

The various boiler accessories will be described in the 
following paragraphs : 

Glass Gauge. This is a glass tube attached to the 
side of the boiler to indicate the height of the water in 
it. It is so attached that its lowest point is about two 
inches above the highest part of the fire line of the boiler, 
its entire length being usually about fifteen inches. The 

159 



160 MARKET DAIRYING 

cock at the bottom is used to blow out the sediment that 
is liable to block the opening between it and the boiler. 
When this occurs the gauge becomes a false indicator. 
Frequent blowing out is therefore necessary. The cock 
next to the blow-out admits the water from the boiler. 
The cock above this admits the steam. When the glass 
breaks shut off the water first, then the steam. Always 
have a few extra glasses on hand so that the broken one 
can be immediately replaced. Owing to its tendency to 
clog, the gauge can not always be relied upon, hence the 
use of water cocks placed next to the glass gauge. 

Water Gauge Cocks; There are three of these used. 
The water level should be kept as near as possible to the 
middle cock. It should never go below the lower cock, 
nor above the upper. These cocks should be opened 
many times during the day, and so long as steam issues 
from the upper and water from the lower cock, the water 
level is all right. 

Steam Gauge. This shows the number of pounds of 
steam pressure per square inch on the boiler by means 
of a pointer moving around a dial. Below the dial is a 
loop which contains water to prevent injury to the gauge 
from the hot steam. The steam gauge is liable to get 
out of order and will then fail to show the true pressure. 
Such a condition is indicated by the safety valve. 

Safety Valve. This is placed on top of the steam 
chamber and permits the escape of steam when the steam 
pressure reaches the danger limit. It is an indispensable 
boiler attachment as without it the boiler would be a 
dangerous thing. There are two kinds of safety valves, 
the "pop" and "ball and lever" types. The former is 
considered the more desirable because it is not so easily 



BOILER AND MANAGEMENT 161 

tampered with. Both can be set to blow off at different 
pressures. 

Water Feed Apparatus. There are two ways of 
feeding water into a boiler, namely, with injectors and 
with pumps. 

Injector. This important boiler 'accessory is attached 
to the side of the boiler. It utilizes the steam 
directly from the boiler for forcing water into it 
against a pressure as great as that which sends it forth. 
The principle which makes this possible may be stated 
as follows : Steam issuing from a boiler under 70 pounds 
pressure has a velocity of 1,700 feet per second. When 
steam with this high velocity strikes the combining tube 
it produces suction which in turn induces a flow of 
water. As soon as the water enters the combining tube 
it is given motion by the high velocity of the steam, 
which immediately condenses and moves with the water 
into the boiler at a comparatively low velocity. The 
energy, therefore, by which steam can force water into the 
boiler against its own pressure is the latent heat resulting 
from the condensation of the steam in the combining tube. 

From this it must be evident that the efficiency of the 
injector is dependent upon the completeness with which 
the steam condenses. This is clearly proven by every 
day practical experience. When, for instance, the feed 
water is too hot, the steam pressure too high, or the 
steam is wet, the injector fails to work properly because 
the steam does not sufficiently condense when it strikes 
the feed water. 

Starting the Injector.- This is done by opening the 
supply water valve one or two turns, then the steam valve 
wide. If steam issues from the overflow admit a little 
more water ; if water overflows admit less. 
11 



162 MARKB7' .DAIRYING 

Care of Injector. An injector will become coated 
with sediment or scale the same as the boiler and must, 
therefore, be frequently cleaned. This is best done by 
immersing it in a solution of one part muriatic acid and 
ten parts water. Allow to remain in this solution until 
the scale becomes soft enough to permit washing out. A 
clean injector rarely causes trouble but if trouble does 
occur it may be due to : (i) low steam pressure; (2) too 
hot water; (3) leaks in pipes and injector; (4) clogging 
of water pipe; (5) wet steam; (6) poor working condi- 
tion of check and overflow valves; (7) clogging of feed 
pipe where it enters the boiler. 

The injector is commonly used to feed water into the 
boiler because it is cheap and simple, and occupies little 
space. 

Pumps. There are two kinds ; ( 1 ) those run with 
steam directly, and (2) those run by the engine. The 
latter is the more economical and handles hot water with 
less trouble. It has one disadvantage, however, and that 
is it does not work unless the engine is running. With 
good pumps, especially those run by the engine, good 
work may be expected when the feed water has been heat- 
ed to 200 F. with the exhaust steam from the engine. 
With the injector such high temperatures are not per- 
missible, hence the greater economy of the pump. The 
great saving of fuel by feeding water hot into the boiler 
is illustrated by experiments made by Jacobus which 
show that with a direct acting pump 12.1% fuel is saved 
by heating the feed water from 6o° to 200 before pump- 
ing it into the boiler. With injectors the feed water used 
usually has a temperature of about 6o° F. 

Steam. Water is practically a non-conductor of heat. 
This means that it cannot conduct its heat to its neighbor- 



BOILER AND MANAGEMENT 163 

ing particles. When, therefore, heat is applied to the bot- 
tom of a vessel containing water, the particles at the 
bottom do not communicate their heat to the particles next 
above them, but expand and rise, cool ones taking their 
places. This gives rise to convection currents which tend 
to equalize the temperature of the water in the vessel. 
When the water has reached a uniform temperature of 
212° F. the particles begin to fly off at the surface in the 
form of vapor, and this we call steam. To generate steam 
in a boiler, then, it is necessary to impart to the water in it 
a considerable amount of heat, which is produced by 
burning fuel in the fire box. 

FIRING OF BOILER. 

The immense amount of heat stored in wood and coal 
is rendered effective in the boiler by burning (combus- 
tion). To understand how to fire a boiler intelligently 
one must first learn what the process of burning consists 
of. 

Process of Burning. Anything will burn when the 
temperature has been raised high enough to cause the 
oxygen of the air to unite with it. Thus, in "striking" 
a match the temperature is raised high enough by the 
friction produced to cause the match to burn. The burn- 
ing match will produce heat enough to ignite the kind- 
ling, y^hich in turn, produces the necessary heat to ignite 
the wood or coal in the fire box of the boiler. Burning 
may, therefore, be defined as the union of the oxygen of 
the air with the fuel. In burning a pound of coal or wood 
a definite amount of air must be admitted to furnish the 
necessary oxygen for complete combustion. When oxygen 
is lacking part of the fuel passes out of the chimney un- 



164 MARKET DAIRYING 

burned in the form of gases'. If, on the other hand, too 
much air is admitted the excess simply passes through 
the chimney, absorbing heat as it passes through the 
boiler. The problem of firing becomes, therefore, a diffi- 
cult one. 

Burning Coal and Wood. When hard coal is burned 
the fire should be thin. A thickness of three to four 
inches on the grates gives very satisfactory results. For 
best results with soft coal a thickness of six to seven 
inches is recommended. Whenever fresh coal is added it 
should be placed near the front and the hot coals pushed 
back. 

In case wood is burned the fire box should be kept well 
filled, care being necessary to keep every part of the grates 
well covered. 

GENERAL POINTERS ON FIRING. 

1. 'Boilers newly set should not be fired within two or 
three weeks after setting and then the firing should be 
very gradual for several days to allow the masonry to 
harden without cracking. 

2. Never fire a boiler before determining the water 
level by trying the water gauge cocks. You can not 
entirely rely upon glass gauges, floats, and water alarms. 

3. When starting the fire, open the upper water gauge 
cock and do not close it until steam begins to issue from 
it. This permits the escape of confined air. 

4. Kindle the fire on a thin layer of coal to protect 
the grate bars. 

5. Always examine the safety valve before starting a 
fire. 

6. When starting the fire all drafts should be open. 



BOILER AND MANAGEMENT 165 

7. The firing should be gradual until, all par.ts of the 
boiler have been heated. 

8. Never allow any part of the grate bars to become 
uncovered during firing. 

9. Frequently clean the ash pit to prevent overheating 
of grates from the hot cinders underneath. 

10. The coals upon the grates should not be larger 
than a man's fist. 

11. Remember that firing up a boiler rapidly is apt to 
cause leaks. 

12. Remember that too little water in. the boiler causes 
leaks and explosions. 

13. Remember that soot and ashes on heating surfaces 
always waste fuel. 

14. When fire is drawn, close dampers and doors of 
furnace and ash pit. 

15. Never open or close valves when the water is too 
low in the boiler, but immediately bank the fire with ashes 
or earth. Opening the safety valve at such a time will 
throw the water from the heated surfaces, resulting in 
overheating and possibly in explosions. 

16. Use the poker as little as possible in firing. 

17. Keep the grate bars free from "clinkers." 

18. When the steam pressure goes too high, start the 
pump, open the doors of the furnace and close the ash 
pit. 

19. A steady and even fire saves fuel. 

GENERAL CARE OE BOILER. 

I. Always close the steam and water valves of the 
glass gauge when you leave the building for half an 
hour or more. 



166 ' MARKET DAIRYING 

2. Water gauges should frequenty be blown out and 
cleaned. 

3. Keep the exterior of the boiler dry. Moisture will 
corrode and weaken it. 

4. The boiler should be blown off under low pressure 
every two or three days. 

5. A boiler that is not used for some time should be 
emptied and dried. If this cannot readily be done, fill 
it full of water to which a little soda has been added. 

6. Frequently examine the safety valve to see that it 
is in good working order. 

7. Do not empty boiler while brick work is very hot. 

8. Never pump cold water into a hot boiler. Leaks 
and explosions may be the result. 

9. Leaky gauges, cocks, valves, and flues should be 
repaired at once. 

10. Do not fail to examine the pressure gauge fre- 
quently. 

11. It is good policy to have two means of feeding a 
boiler. The pump or injector may get out of order and 
cause delay and danger. 

12. Feed pumps and injectors need frequent cleaning 
to keep them in good working order. 

13. Look out for air leaks. If air is admitted any- 
where except through the grates serious waste may re- 
sult. Such leaks are to be looked for in broken doors and 
poor brick work. 

14. Flues should be cleaned often, especially if soft 
coal is burned. This will prevent overheating of metal 
and at the same time save fuel. 

15. Do not allow filth to accumulate around the boiler 
or boiler room. 

16. Keep all the bright work about the boiler "shiny." 



BOILER AND MANAGEMENT 167 

17. Do not fail to empty the boiler every week or two 
and refill with fresh water. 

18. Have your steam gauge tested at least twice a 
year. 

BOILER INCRUSTATION* 

In all boilers after a period of use, there is deposited 
upon the parts below the water level a scale or sediment 
known as boiler incrustation. 

Cause of Scale. The formation of scale is due to 
the impurities contained in the feed water. When impure 
water is fed into the boiler the impurity first manifests 
itself in the form of scum on top of the boiling water. 
The heavier particles of the scum slowly unite and sink 
to the bottom where they first appear as mud. By con- 
tinued exposure to high temperature, this mud gradually 
forms into a hard impervious scale which usually con- 
sists largely of lime. 

Objection to Scale. 1. The excessive formation of 
boiler scale is the immediate cause of most boiler explo- 
sions. The scale acts as a non-conductor of heat, so that 
in cases where the capacity of the boiler is severely taxed, 
the metal becomes overheated, thus materially weakening 
it. The scale is, therefore, not only dangerous, but by 
overheating the metal, also materially shortens the life 
of the boiler. 2. Another most serious objection to scale 
is its wastefulness of fuel. This becomes evident when 
we note that the heat before reaching the water must first 
be conducted through a non-conducting layer of incrusta- 
tion. 

Prevention of Scale. Since nearly all water used for 
boilers is more or less impure, it is evident that to prevent 
scale, boilers must receive frequent cleaning. How often 



168 MARKET DAIRYING 

this needs to be done is, of course, dependent upon the 
amount and character of the impurity in the water. Boilers 
are kept clean in three different ways, (i) by blowing 
off at low pressure, (2) by cleaning through manhole, 
and (3) by using boiler compounds. 

(1). By blowing the boiler off at low pressure most 
of the mud will be blown out. But care must be taken 
that the pressure is not above ten pounds and that there is 
no more fire in the fire box, otherwise the mud, instead 
of flowing out with the water, will bake on and form 
scale. 

(2). A good way of removing mud is to allow the 
boiler to cool off and then run a rubber hose through the 
manhole. By working the hose and forcing water 
through it the sediment can be removed. 

(3) Boiler compounds are used to keep boilers free 
from scale. The kind of compound to be used is deter- 
mined by the character of the impurities of the water. 
Most dairies use well water for the boiler and the chief 
impurity in this is lime. The best compound for water 
of this kind is soda. Well water contains the lime in 
widely different proportions. In order, therefore, to as- 
certain the proportion of soda to feed water the following 
method is recommended by Hawkins: 

"1. Add one sixteenth part of an ounce of soda to a 
gallon of the feed water and boil it. 2. When the sedi- 
ment thrown down by the boiling has settled to the bottom 
of the kettle, pour the clear water off and add one-half 
drachm of soda to this. Now, if the water remains clear, 
the soda which was put in has removed the lime. But 
if it becomes muddy, the second addition of soda is neces- 
sary." In this way the amount of soda to be added to 
the feed water can be calculated with sufficient accuracy. 



BOILER AND MANAGEMENT 169 

Tan bark is very efficient in removing boiler scale but 
may injure the iron. 

Kerosene answers the same purpose but renders the 
steam unfit for use in the dairy. 

When the water is salt or acid, a piece of metallic zinc 
occasionally placed in the boiler will prevent corrosion. 
Water of this kind can usually be told by its corrosive 
effect on copper and brass. Acid water can also be de- 
tected with blue litmus paper, which it turns red. 

WET AND DRY STEAM. 

Wet Steam. This is steam holding in suspension ex- 
tremely small particles of water which are thrown off 
from the water surface while steam is generating. The 
following are the causes of wet steam : 

i. Impure water in the boiler. 

2. Too much water in the boiler. 

3. Too little evaporating surface for the amount of 
steam used. This is one of the chief objections to upright 
and too small boilers. 

4. Violent agitation of the water in the boiler caused 
by too rapid a generation of steam. 

Wet steam causes "priming" and is wasteful of heat. 

Dry Steam. This is saturated steam holding no water 
mechanically in suspension. High steam pressure and a 
large steam space above the water level are conducive 
to dry steam. 



CHAPTER XXV. 

WATER AND ICE SUPPLY. 
WATER SUPPLY 

Importance of Pure Water. A great deal of disease 
in farm homes is directly traceable to infected water. 
Typhoid fever especially is so frequently caused by pol- 
luted well water that physicians at once look to this as 
the probable cause wherever this disease is found to ex- 
ist. 

Where wells infected with disease germs happen to ex- 
ist on dairy farms that supply milk to neighboring cities, 
disease is not limited to the dairyman's own family, but 
may be spread along the entire milk route. Many typhoid 
fever epidemics have been positively traced to milk which 
has become infected through water containing the disease 
germs. Nowhere is pure water so important, therefore, 
as upon dairy farms. 

The disease germs usually find their way into the milk 
through milk vessels which have been washed with in- 
fected water. The use of such water for washing cows' 
udders previous to milking may also be the means of in- 
fecting the milk supply. 

Location of Well. The most satisfactory location for 
the well is at the dairy house where the coldest water is 
required and where it will be most convenient. Here the 
water for both the dairy, the home, and the stock can be 
pumped with the dairy engine. Further, the well, like 

170 



WATER AND ICE SUPPLY 



171 



the dairy house, should stand on slightly elevated ground 
so as to insure drainage away from it. 

Construction o£ Well. In a properly constructed 
well, no water should enter it except near the bottom. 
This compels the water to pass through a thickness of 
earth sufficient to purify it where the wells are of a 
reasonable depth. 

Where there is no rock or hard clay and where the 




Fig. 62.— Soil Strata. (From Harrington's "Practical Hygiene.") 

water can be had at a reasonable depth, the driven well, 
commonly knov/n as the Abyssinian tube well, is the 
cheapest and one of the safest. This well is made by 
driving into the ground a water-tight iron tube, the lower 
end of which is pointed and perforated. 

In case rocks and hard clay must be penetrated, or great 
depth must be reached to secure water, the bored or 
drilled well, piped from top to bottom with water-tight 
iron pipes, will be found most satisfactory. 



172 



MARKET DAIRYING 



Water from the upper pervious stratum should be 
avoided wherever possible, even with wells of the kind 
just described. Especially is this necessary where the 
wells are shallow. The purest water is obtained by sink- 
ing the well through an impervious stratum, like that 
shown in Fig. 62. 

The most dangerous well is the common dug well with 
pervious walls and so located as to permit seepage into 
it from outhouses, barnyards and cesspools. Wells of 
this type are altogether too common on dairy farms. 




Fig. 63.— Sources of Well Water Contamination. (From Bui. 143 Kan. 

Exp. Sta.) 

All wells, whatever their construction, must be provided 
with water-tight metallic or concrete covers to prevent 
the entrance of impurities into the shaft. 



ICE SUPPLY. 

Necessity of Ice. Where there is no equipment for 



WATER AND ICE SUPPLY 173 

mechanical refrigeration, ice is indispensible in furnish- 
ing the best quality of milk and cream. A low enough 
temperature cannot be secured with water alone, neither 
can the cooling be accomplished as quickly as is desirable 
for best results. Furthermore, a satisfactory cold storage 
cannot be had without the use of ice. 

Cooling Power of Ice. A great deal of cooling can 
be done with a comparatively small amount of ice. This 
is due to the latent or "hidden" cold in ice. Thus to 
convert one pound of ice at 32 ° F. into water at the same 
temperature requires 142 units of heat, or, in other words, 
enough cold is given out to reduce the temperature of 
142 pounds of water one degree Fahr. 

Construction of Ice House. To keep ice satisfactorily 
three things are necessary, ( 1 ) good drainage at the bot- 
tom, (2) good insulation, and (3) abundant ventilation 
at the top. 

Good drainage and insulation at the bottom can be se- 
sured by laying an eight-inch foundation of stones and 
gravel and on top of this six inches of cinders, the whole 
being underlaid with drain tile. One foot of sawdust 
should be packed upon the cinders and the ice laid directly 
upon the sawdust. 

Satisfactory walls are secured by using matched boards 
on the outside of the studs and common rough boards 
on the inside, leaving the space between the studs empty. 
The ice should be separated from the walls by one foot of 
sawdust. 

Where no solid foundation walls are provided, earth 
must be banked around the ice house to prevent the en- 
trance of air along the base. 

The space between the sawdust covering on top of the 
ice and the roof should be left clear. Openings in the 



174 MARKET DAIRYING 

gable ends as well as one or two ventilating shafts pro- 
jecting through the roof should be provided to insure a 
free circulation of air under the roof. This will not only 
remove the hot air which naturally gathers beneath the 
roof, but will aid in drying the sawdust. 

The ice must be packed solidly, using no sawdust 
except at the sides and bottom of the ice house and on 
top of the ice when the filling is completed. At least one 
foot of sawdust must be packed on top of the ice. 

Size of Ice House. The size of the ice house will 
depend, of course, upon the amount of ice to be used. 
For a herd of 25 cows, in the North, an ice house 10 
feet square by 14 feet high will usually answer. These 
dimensions provide storage for 22 tons of ice, allowing 
one-foot space all around the ice for sawdust. In the 
South about 50% more ice is required than in the North. 

In calculating the amount of storage space needed for 
ice, it is necessary to know that one cubic foot of ice at 32 ° 
F. weighs 57.5 pounds. 

As a matter of convenience in filling and emptying the 
ice house, doors should be provided in sections from the 
sill to the gable at one end of the building. 

General Uses of Ice. Aside from the use of ice in 
cooling milk and cream, it can be employed to good ad- 
vantage in several other ways. Its value in the house- 
hold, in preserving meats, vegetables, and fruits cannot 
be overestimated. And what is so refreshing as cold 
drinks and frozen desserts during the summer months ! 
Ice is also frequently necessary in case of sickness. 

Cost of Making Ice. Where ice can be obtained with- 
in a reasonable distance, the cost of cutting, hauling, and 
packing should not exceed $1.50 per ton. 

Source of Ice. Always select the cleanest ice available. 



WATER AND ICE SUPPLY 175 

Where the source of ice is at too great a distance from 
the dairy, an artificial pond should be made upon ground 
with a reasonably impervious subsoil and with a natural 
concave formation. If such a piece of ground is flooded 
with water during the coldest weather, an ample supply 
of ice will be available in a very short time. 



CHAPTER XXVI. 

SEWAGE DISPOSAL FROM DAIRY AND DWEEUNG. 

To secure a high degree of sanitation in and about 
the dairy house it is necessary to see that proper 
disposal is made of the sewage from both the dairy and 
the dwelling. Where the latter is situated close to the 
dairy house its surroundings may do fully as much harm 
as those of the dairy itself. 

With open privies and the careless dumping of kitchen 
slops near the dwelling, we have a double means of en- 
dangering the dairy. If the ground near the dwelling 
and privy slopes in the direction of the water supply, the 
latter is likely to become contaminated through seepage in 
the manner indicated in Fig. 63. In addition to this there 
is the danger of flies carrying various kinds of bacteria 
from these places to the dairy house. Flies not only carry 
the obnoxious, putrefactive species, but too often also 
the deadly pathogenic kinds, such as cause typhoid fever, 
to say nothing of the offensive excrementitious matter 
conveyed in this manner. 

Obviously the accumulation of sewage about the dairy 
house is attended by practically the same danger as that 
arising from the unsanitary surroundings of the dwelling. 
Moreover there is certain to be trouble also from bad 
odors. 

SEPTIC TANK. 

The best means of taking care of the sewage from 
176 



SEWAGE DISPOSAL 



111 



both the dairy and the dwelling is to run it into a septic 
tank (see Fig. 64, designed by the author) and from 
this into a net-work of tile laid underground where it 
will irrigate and fertilize the soil. 

Object of Septic Tank. The main purpose of the 
tank, as its name indicates, is to thoroughly decompose 
all organic matter entering it. This is accomplished by 
numerous species of bacteria, and the tank may be 
properly designated as a germ incubator. Where the 




Fig. 64.— Septic Tank. 

sewage is emptied into underground tile, the tank also 
serves as a storage, discharging its contents intermittently. 
This is necessary to force the liquid to all points of the 
system and to allow time for each discharge to soak away 
before the appearance of the next. 

Construction of Tank. The general plan of construc- 
tion is illustrated in Figs. 64 and 65. The tank is located 
in the ground with the top within a foot or two of the 
surface. For durability it is preferably constructed of 
brick, stone or concrete. The tank is so constructed as to 
12 



178 



MARKET DAIRYING 



retain all sediment and floating material, since the dis- 
charges permit the withdrawal of the liquid from near the 
middle of the tank only. This is one of the main features 
of the tank. All inorganic matter entering the tank will 
gradually settle and, of course, remain in it. Some of 
the organic matter tends to settle during the first 24 hours, 

„ ,, „„ ir f ,„ after which it comes to the 

surface to be gradually 
wasted away by the action 
of bacteria. This wasting 
away is naturally very 
slow, and since the slowly 
gathering organic matter 
nearly all remains in the 
first section of the tank, 
this must be large enough 
to provide for a consider- 
able accumulation of it. 

The tank should be built air tight, except in two places. 
At the right is an air inlet, consisting of a goose-neck 
pipe, which renders the vent at the top more effective. 
This vent consists of a long shaft extending beyond the 
top of the dairy, thus carrying off the foul gases caused 
by the decomposition of the material within. One-inch 
gas pipe, properly fastened, will serve as a satisfactory 
vent. 

In order to afford communication of sections A and C 
with the vent, the two partitions should not be built 
quite as high as the tank. There should be at least one 
inch space between the top of the partitions and the cover. 
A 1 1 / 2 -inch gas pipe should be laid over the tank 
through which the water from the cooler and vats may 
be discharged directly into the drain. This water 



Fig. 65.— Cross Section of Septic 
Tank. 



SEWAGE DISPOSAL 179 

requires no purification and, if conducted through the 
tank, would necessitate one of too large dimensions. 
Moreover, the large amount of cold water needed for 
cooling milk and cream would cool the contents of the 
tank too much for a rapid decomposition of the material 
within. 

Size of Tank. This must necessarily depend upon the 
amount of sewage run into it. In general it should have 
capacity sufficient to hold all of one day's waste in the 
smallest section (C). It will be noticed from the cut 
that section A is considerably larger than either of the 
other two. The reason for this is that nearly all of the 
inorganic matter remains in the bottom of this part of the 
tank, while the organic matter, as already stated, gradu- 
ally accumulates at the surface in this section, in spite 
of constant decomposition. Where the tank receives the 
sewage from both the dairy and the dwelling, a tank 
12 feet square by 4^ feet deep will be large enough, 
provided the water used for cooling is not run into it. 
It is well to remember, however, that the larger the tank 
used the better the results that may be expected from it. 

Flow of Sewage Through Tank. Four-inch tile, 
carefully laid, may be used to conduct the sewage from 
the dairy to the tank. A trap is placed near the dairy 
to shut off the odors coming from the drain. At the 
point at which the sewage enters the tank it is desirable 
to attach an elbow with an arm sufficiently long to keep 
the lower end always in the sewage. This prevents un- 
due mixing of the incoming sewage with that already 
in the tank, a matter of importance in the successful 
operation of the tank. 

When the sewage in section A has reached the dotted 
line, it begins to discharge into section B through three- 



180 MARKET DAIRYING 

inch gas pipe as shown in Fig. 64. The liquid is with- 
drawn from a point near the middle of the tank as in- 
dicated by the discharge pipes. The eight-inch space 
above the discharge permits the accumulation of organic 
matter. The discharge from B into C, is the same as 
that from A into B ; but the discharge pipes are of neces- 
sity lower by an amount indicated by the dotted lines. 
Compartment C discharges intermittently by means of 
an automatic syphon. 

The sewage becomes gradually purified in its passage 
through the tank, and as it flows from the last section 
it is nearly as clear as water, but has a slightly sour odor, 
which it seems to retain and which is in no way objection- 
able. The purified sewage has been kept for weeks with 
no sign of the development of putrefactive odors. 

The discharges should be arranged as shown in Fig. 
65. This arrangement will cause the least mixing of old 
and new sewage. There is no discharge from A into B 
until the second day's sewage flows into A. Similarly 
there is no discharge from B into C until the second 
discharge into B, etc. The sewage, therefore, requires 
from three to four days in its passage through the tank. 

Cost of Septic Tank. A double partition tank, 12 
feet square and 4^ feet deep, constructed of concrete 
consisting of one part cement, two parts sand and four 
parts gravel, will cost approximately $50.00 when the 
walls are five inches thick. 

SEW AGE. DISPOSAL FROM DWELLING. 

The open privy and the cesspool of kitchen slops are 
objectionable not only in so far as they affect the dairy 
house, but also in that they constitute a source of danger 
to the members of the family in ways entirely discon- 
nected with the milk supply. With the dairy house 



SEWAGE DISPOSAL 181 

already equipped with power to pump and elevate water, 
there is apparently no reason why the dwelling should 
not be equipped with a water closet. And with a water 
closet in the house there would be practically no expense 
connected with the disposal of the kitchen waste, since 
this would be discharged directly into the soil pipe con- 
nected with the closet. What a convenience such an 
equipment would afford to the housewife and members of 
the family! 

If the dwelling and dairy house are reasonably close 
together, one septic tank will answer for both. In such 
a case the tank is located between the two buildings. 
Where a great distance separates the buildings, a tank 
is provided for each and the outlets are brought together 
as near the tank as possible to save extra expense of tile. 

SUBSURFACE) IRRIGATION. 

While the septic tank sufficiently decomposes the 
organic matter to leave the sewage from the tank without 
offensive odors, it is best to run the discharge into a 
system of underground tile where it will serve as a fer- 
tilizer and as an irrigating agent. The tile should be 
laid below the frost line. In loose soils one foot of tile 
per gallon of sewage will answer. Clayey soils require 
two to three times this amount. 

Three-inch agricultural drain tile are best adapted for 
drainage work of this kind, the tile being laid with open 
joints and with a slope of three or four inches per hundred 
feet. 

It is important that this subsurface irrigating system 
be located where there is no seepage into the water supply. 
In places where there is no danger from frost it is best 
to lay the tile only about one and one-half feet below the 
surface. . 



APPENDIX. 

Relationship of Fat and Solids=not=Fat. In normal 
milk a fairly definite relationship exists between the fat 
and the solids-not-fat. That is, milk rich in fat is like- 
wise rich in solids-not-fat. This is an important point 
for the consumer to bear in mind, because when he buys 
milk rich in fat he gets milk which is also rich in the 
more important food constituents, namely, the proteids. 

Composition of Cream. Cream contains all the con- 
stituents found in milk, though not in the same proportion. 
The fat may vary from 8% to 68%. As the cream grows 
richer in fat it becomes poorer in solids not fat. This is 
illustrated in the following figures by Richmond: 



Total solids. 


Solids 
not fat. 


Fat. 


Per cent. 


Per cent. 


Per cent. 


32.50 




6.83 


25.67 


37.59 




6.14 


31.45 


50.92 




5.02 


45.90 


55.05 




4.65 


50.40 


57.99 




4.17 


53.82 


68.18 




3.30 


64.88 



The same authority also reports the following detailed 
analysis of a thick cream : 

182 



APPENDIX 



183 



Per cent. 

Water 39.37 

Fat 56.09 

Sugar 2 . 29 

Proteids 1 . 57 

Ash 38 

Composition of Buttermilk. According to Vieth, 
buttermilk from ripened cream has the following compo- 
sition : 

Per cent. 

Water 90.39 

Fat 50 

Milk sugar 4.06 

Lactic acid .80 

Proteids ■ 3 . 60 

Ash 75 

Dairy buttermilk should not average above .2% fat. 
Composition of Skim=milk. Richmond has found 
the following average composition of separator skim- 
milk: 

Per cent. 
Water 90 . 50 



Fat 

Milk sugar 4 

Casein 3 

Albumen 

Ash 



COMPARISON OF CENTIGRADE AND FAHRENHEIT THER- 
MOMETER SCALES. 



Thermometer. 


F. 


C. 




212 
32 


100 











Difference between boiling and freezing point 


180 


100 



184 



MARKET DAIRYING 



From the above it will be seen that one degree Centi- 
grade is equivalent to 9-5 degrees Fahrenheit. Hence 
the following rules: 

1. To change C. into F. reading, multiply by 9-5 and 
add 32. 

Example: 50°C = (50 X f ) + 32 = 122°F. 

2. To change F. into C. reading, subtract 32 and 
multiply by 5-9. 

Example: 182°F = (182 — 32) X f =83*°C. 

METRIC SYSTEM OF WEIGHTS AND MEASURES. 

This system was devised by the French people and has 
very extensive application wherever accuracy in weights 
and measures is desired. Some of its equivalents in 
ordinary weights and measures are given in the follow- 
ing table : 



Ordinary weights and measures. 


Equivalents in metric system. 




28.35 prams. 




0.9464 liter. 




3.7854 liters. 




29.57 cubic centimeters (c.c.) 
0.4536 kilogram. 






64.8 milligrams. 






1 foot 


0.3048 meter. 







APPENDIX 
LINING UP SHAFTING. 



185 



Fasten a heavily chalked string along the ceiling paral- 
lel to the direction the shafting is to take. Snap the 
string, and a white mark will indicate the position of the 
shafting in a plane parallel to the floor. This plane is 
indicated by the line ab in Fig. 66. Next determine the 
position of the shafting in a plane at right angles to the 



<$ 



e 



D 




Fig. 66.— Intersecting Planes. 



Fig. 67.— An Aid to Lin- 
ing up Shafting. 



floor, indicated by the line cd. This is done as follows : 
Loosely fasten the hangers along the white chalk line 
and properly fasten the shafting. Now hang on the shaft- 
ing, at intervals of three feet, pieces of board like that 
shown in Fig. 67. The upper end is rounded to fit over 
the shaft, while the lower end is perforated as indicated 
in the Fig. These pieces of board must be carefully cut 



186 MARKET DAIRYING 

so that the distance P is the same in all. If the holes 
at the lower ends are all in line the shafting is properly 
lined up. If not, the shaft needs readjusting. 

CALCULATING SIZE AND SPEED OF PULLEYS. 

The first thing to remember in determining the required 
size and speed of pulleys is the following rule : The speed 
varies inversely with the diameter of the pulley. Thus 
with the same speed of the engine, the speed of the main 
shaft becomes less as the diameter of the pulley on that 
shaft is increased. 

We usually speak of two kinds of pulleys: the drive 
pulley and the driven pulley. Where the engine drives 
the main shaft the pulley on the engine is called the drive 
pulley and that on the main shaft the driven pulley. 
When we refer to the main shaft driving the separator, 
then the pulley on the main shaft becomes the driver and 
that on the separator the driven pulley. 

In dairies there are two problems that present them- 
selves with respect to pulleys : one is to find the speed of 
the pulley when the diameter is given ; the other is to 
find the diameter when the speed is given. 

1. To find the speed of a driven pulley: Multiply the 
diameter of the driver by its speed and divide the product 
by the diameter of the driven pulley. 

Example : Diameter of engine pulley, 20 inches ; speed 
of engine 200 revolutions per minute ; diameter of driven 
pulley, 25 inches. 

20 X 200-^25=1 6o=No. rev. per min. of driven pulley. 

2. To find the diameter of driven pulley : Multiply the 



APPENDIX 187 

diameter of driver by its speed and divide the product 
by the required speed of driven pulley. 

Example : Diameter of engine pulley, 20 inches ; speed 
of engine, 200 revolutions per minute; speed of driven 
pulley, 200 revolutions per minute. 

20 X 200 -v- 200 = 20 = diameter of driven pulley. 

CARE AND MANAGEMENT OE ENGINE. 

1. It is essential to have all parts of the engine well 
oiled, using nothing but the best oil. 

2. Keep the engine clean. The shiny parts should be 
brightened at least once a day. 

3. Keep the engine well ''keyed up." At both ends 
of the connecting rod are keys, the purpose of which is to 
keep the brass boxes tight enough to prevent undue play. 
The "keying" consists in loosening the burrs next to the 
key and then tapping the latter lightly until the unneces- 
sary play is taken up. Care must be taken, however, not 
to get the brasses too tight or a hot box will be the result. 
"Pounding" is usually caused by not having the keys 
properly set. It is also caused by wet steam and water in 
the cylinder. 

4. Keep stuffing boxes carefully packed to prevent 
leakage of steam. The packing should be treated with 
graphite or good cylinder oil and packed firmly around 
the rod, but it must not be too tight, otherwise power 
is lost in friction. If the rod has become scored or rusty, 
smooth it with emery cloth before packing. 

5. The packing rings in the piston should be kept in 
good repair. The clicking noise sometimes heard in 
cylinders is due either to the packing ring wiping over 



188 



MARKET DAIRYING 



the edge of the counter bore or to its being too narrow 
for the groove in which it is placed. A ring is needed 
that fits this groove properly. If the packing ring is too 
small for the cylinder bore it should be set out by peneing 
or by tightening the setting out bolts. 

6. When gumminess is noticeable in any of the bear- 
ings, remove same with benzine and use a purer oil. 

7. When the engine "races" look for the trouble in 
the governor. 

8. Thoroughly drain cylinder when not in use. This 
must be done in the winter to prevent freezing. 





Bottle Sealed with Metallic Cap. 



Metallic Milk Bottle Cap. 



INDEX. 



Page 

Accounts, keeping 146 

Acidity of cream 115 

Acid measures 46 

Acid tests for cream 115 

Aeration of milk and cream.... 33 

importance of 34 

Albumen 13 

Albumenoids 12 

Appendix 182 

Ash 13 

Babcock test 42 

apparatus for 44 

precautions in making 49 

principle of 42 

sample for 42 

Babcock testers 43 

Bacteria, disease producing 21 

lactic acid 20 

taint producing 21 

Bacteria in milk 10 

Barn air 20 

Barn, sanitary 24, 154 

Barn yard 25 

Bedding 30 

Boiler, care of 165 

firing of 163 

Boiler management 150 

Boiler scale 167 

Bottle cases 75, 76 

Bottle crate 80 

Bottle filler 74 

Bottle washer 83 

Brine, strength of 130 

Brushes 83 

Burning, process of 163 

Butter carton 128 

Butter, composition of 128 

marketing of 127 

value of 108 

working of .... . 124 

yield of 108 



Page 

Butterfat, composition of 10 

physical properties of 9 

Buttermaking, farm Ill 

Buttermilk, composition of 183 

food value of 00 

Buttermilk, skim-milk 08 

marketing of 99 

Butter print boxes 127 

Butter printer 125 

Butter salting 123 

Butter worker 125 

Can jacket 78 

Cans „ 78, 79 

Casein . . : 12 

Certified milk 154 

definition of 154 

production of 155 

uses of 155 

Cheese, yield of 108 

value of 108 

Churning 117 

difficult 126 

influences affecting 118 

steps in 121 

temperature in 118 

Churns 121 

cleaning 126 

Cold storage 62 

Composition of milk of different 

breeds 17 

Compressor 140 

power required to operate.. 140 

size of 140 

Cooler, cone-shaped 30 

corrugated 35 

method of attaching. ... 36 

tubular 38, 39 

Coolers 35 

Cooling, importance of 33 

precautions in 40 



189 



190 



INDEX 



Page 

Cooling milk and cream 33 

value of prompt 34 

with brine 39 

with ice, data on 37 

with pump 37 

Cottage cheese . 90 

food value of 97 

making of 90 

marketing of 96 

packages for 95 

yield of 96 

Cows, clean 25 

health of 23 

Cream, bottling of 74 

composition of 182 

coolers 35 

pasteurization 151 

regulating richness of 56 

retailing of 73 

ripening Ill 

control of 113 

objects of Ill, 112 

starters in 114 

scales for 47 

shipping of. 78 

standardizing of 59 

test bottle for 45 

testing acidity of 117 

value of 107 

yield of 107 

Creaming 52 

centrifugal 54 

Cooley can for 53 

deep, cold method of 53 

efficiency of 54 

processes of 52 

shallow pan 52 

Dairy house 129 

construction of 129 

floor plans for 129 

screening of 135 

warming of 134 

Dairy thermometer 120 

Delivery cases 75, 76 

Delivery of milk 77 



Page 
Engine, management of 187 

Fat and solids not fat ...182 

Fats, insoluble 11 

soluble 12 

Feeds, clean, wholesome....... 28 

Firing, pointers on 164 

Flies 31 

Fore-milk 30 

Ice box 62, 63 

Ice, cooling power of... 173 

cost of making 174 

general uses of 174 

necessity of 172 

source of 174 

supply of 172 

Ice cream 101 

lemon 102 

making of 101 

marketing of 105 

overrun in 105 

packing of 103 

packing can for 104 

packing tub for 104 

vanilla 102 

Ice house 173 

construction of 173 

size of 174 

Injector 161 

Jackets, felt 78 

Ledger 148 

Lemon ice cream 102 

Markets 69 

Mechanical refrigeration 136 

Metric system 184 

Milk 7 

bacteria in 19 

bottling of 74 

cans 78, 79 

care of, in home 157 

certified 154 

colostrum 14 

composition of 8 



INDEX 



191 



Page 

Milk coolers 35 

deliveries 77 

delivery wagons 77 

experimental data on pro- 
duction of clean 31 

pasteurization of 151 

physical properties of 7 

retailing of 73 

sanitary production of 23 

secretion of 14 

shipping of 78 

standardizing of 50 

sugar 13 

tickets 146 

value of 107 

variations in quality of . . . . 15 
Milk and its products, tahle of 

values for 109 

Milk bottle 73 

cap 75 

cases 75, 76 

crates 89 

filler 74 

Milk can jackets 78 

Milk of different breeds 17 

Milk pail, sanitary 27 

Trueman 155 

Milk test bottle 45 

Milk vessels, sterilizing of 84 

washing of 83 

Milkers, clean 26 

Pasteurization 151 

inefficient 153 

methods of 151 

Pasteurizing at home 153 

Pasteurizing temperature 152 

Pipette 46 

Pulleys, determining speed of.. 186 

Pump, boiler feed 162 

Pure cultures 90 

Refrigerating capacity 140 

Refrigerating pipes 141 

Refrigerating plant, charging of. 141 

Refrigeration, mechanical 136 

circulation of ammonia in.. 137 



Page 

Refrigeration, expense of 141 

systems of 138 

Refrigerator 68, 65 

cooled with ammonia . 67 

with brine 139 

with ice 66, 68 

for small dairymen 62, 63 

Route book 148 

Safety valve 160 

Seal press 81 

Seals, lead 81 

metallic 188 

Separator, hand 55, 54 

efficiency of 54 

fastening of 57, 58 

value of 56 

Separators, water 53 

Septic tank 176, 177 

construction of 177 

cost of 180 

size of 179 

Sewage disposal 176 

from dwelling 180 

subsurface 181 

Shafting, lining up 185 

Shipping milk and cream 78 

Sink, wash 82 

Skim-milk bottle 45 

Skim-milk, composition of 183 

Starters 90 

Statement, monthly 149 

Steam 162 

Steam gauge 160 

Steam, wet and dry 169 

Sterilizer, concrete 86 

Sterilizing . 84 

Sterilizing truck 85 

Strainers 29 

Straining 29 

Supplies, order book for 150 

Test, Babcock 42 

Test bottles, cleaning 51 

Test, cream, how to read 51 

milk, how to read 48 

Testers, Babcock 43 



192 



INDEX 



Page 

Testing, pointers on 50 

Thermometer 120 

Thermometer scales, comparison 

of 183 

Tickets, milk 14G 

Trap, bell 134 

Vanilla bean 101 

flavor 101 

ice cream making 102 



Page 

Vessels, clean 26 

Viscogin 152 

Washing vessels 82 

Water heater 84 

Water, pure 28 

supply 170 

Well, construction of 171 

location of 170 



jM 16 19U9 



